********* Functions ********* Functions in Ride are declared with func, function must be declared above the place of its usage. When declaring a function to the right of the "=" sign must be an :ref:`expression <03_ride-language/01_syntax-basics:Expressions>`. The value of the function is the expression result. Definition of the function with no parameters that returns an integer: .. code-block:: none func main() = { 3 } Definition of a function with two parameters: .. code-block:: none func main(amount: Int, name: String) = { throw() } Functions do have return types, this is inferred automatically by the compiler, so you don't have to declare them. There is no return statement in the language because Ride is expression-based (everything is an expression), and the last statement is a result of the function. .. code-block:: none func greet(name: String) = { "Hello, " + name } func add(a: Int, b: Int) = { func m(a:Int) = a m(a) + b } The type (Int, String, etc) comes after the argument’s name. As in many other languages, functions should not be overloaded. It helps to keep the code simple, readable and maintainable. Functions can be invoked in prefix and postfix order: .. code-block:: none let list = [1, 2, 3] let a1 = list.size() let a2 = size(list) let b1 = getInteger(this, "key") let b2 = this.getInteger("key") Annotations =========== Functions can be without annotations, but they can also be with @Callable or @Verifier annotations. Annotated functions are used only in scripts of type DAPP. Here’s an example of @Callable: .. code-block:: none {-# STDLIB_VERSION 5 #-} {-# CONTENT_TYPE DAPP #-} {-# SCRIPT_TYPE ACCOUNT #-} func getPayment(i: Invocation) = { if (size(i.payments) == 0) then throw("Payment must be attached") else { let pmt = i.payments[0] if (isDefined(pmt.assetId)) then throw("This function accepts DecentralCoin tokens only") else pmt.amount } } @Callable(i) func pay() = { let amount = getPayment(i) ( [ IntegerEntry(toBase58String(i.caller.bytes), amount) ], unit ) } Annotations can bind some values to the function. In the example above, variable i was bound to the function pay and stored some fields of the invocation (the caller’s public key, address, payments attached to the invocation, fee, transaction ID etc.). Functions without annotations are not available from the outside. You can call them only inside other functions. Here’s an example of @Verifier: .. code-block:: none @Verifier(tx) func verifier() = { match tx { case m: TransferTransaction => tx.amount <= 100 # can send up to 100 tokens case _ => false } } A function with the @Verifier annotation sets the rules for outgoing transactions of a decentralized application (dApp). Verifier functions cannot be called from the outside, but they are executed every time an attempt is made to send a transaction from a dApp. Verifier functions should always return a Boolean value as a result, depending on whether a transaction will be recorded to the blockchain or not. Expression scripts (with directive {-# CONTENT_TYPE EXPRESSION #-} along with functions annotated by @Verifier should always return a boolean value. Depending on that value the transaction will be accepted (in case of true) or rejected (in case of false) by the blockchain. .. code-block:: none @Verifier(tx) func verifier() = { sigVerify(tx.bodyBytes, tx.proofs[0], tx.senderPublicKey) } The Verifier function binds variable tx, which is an object with all fields of the current outgoing transaction. A maximum of one @Verifier() function can be defined in each dApp script. Callable Functions ================== The functions with the @Callable annotation become callable functions, since they can be called (or invoked) from other accounts: by an Invoke Script transaction or by a dApp. A callable function can perform actions: write data to the dApp data storage, transfer tokens from the dApp to other accounts, issue/release/burn tokens, and others. The result of a callable function is a tuple of two elements: a list of structures describing script actions and a value passed to the parent function in case of the :ref:`dApp-to-dApp invocation <03_ride-language/07_dapp-to-app-invocation:dApp-to-App Invocation>`. .. code-block:: none @Callable(i) func giveAway(age: Int) = { ( [ ScriptTransfer(i.caller, age, unit), IntegerEntry(toBase58String(i.caller.bytes), age) ], unit ) } Every caller of giveAway function will receive as many Decentralites as their age. The ScriptTransfer structure sets the parameters of the token transfer. dApp also will store information about the fact of the transfer in its data storage. The IntegerEntry structure sets the parameters of the entry: key and value. Built-in Functions ================== A built-in function is a function of the standard library . Account Data Storage Functions ------------------------------ Learn more about :ref:`account data storage <02_decentralchain/01_account:Account Data Storage>`. .. csv-table:: Account Data Storage Functions :file: ../_static/03_ride-language/tables/012_Account-Data-Storage-Functions.csv :header-rows: 1 :class: longtable :widths: 5 4 1 getBinary(Address|Alias, String): ByteVector|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets an array of bytes by key. .. code-block:: none getBinary(addressOrAlias: Address|Alias, key: String): ByteVector|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/013_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getBinary(String): ByteVector|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets an array of bytes by key from the dApp's own data storage. .. code-block:: none getBinary(key: String): ByteVector|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/014_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getBinaryValue(Address|Alias, String): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets an array of bytes by key. Fails if there is no data. .. code-block:: none getBinaryValue(addressOrAlias: Address|Alias, key: String): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/015_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getBinaryValue(String): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets an array of bytes by key from the dApp's own data storage. .. code-block:: none getBinaryValue(key: String): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/016_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getBoolean(Address|Alias, String): Boolean|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a boolean value by key. .. code-block:: none getBoolean(addressOrAlias: Address|Alias, key: String): Boolean|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/017_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getBoolean(String): Boolean|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a boolean value by key by key from the dApp's own data storage. .. code-block:: none getBoolean(key: String): Boolean|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/018_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getBooleanValue(Address|Alias, String): Boolean ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a boolean value by key. Fails if there is no data. .. code-block:: none getBooleanValue(addressOrAlias: Address|Alias, key: String): Boolean :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/019_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getBooleanValue(String): Boolean ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a boolean value by key from the dApp's own data storage. .. code-block:: none getBooleanValue(key: String): Boolean :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/020_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getInteger(Address|Alias, String): Int|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets an integer by key. .. code-block:: none getInteger(addressOrAlias: Address|Alias, key: String): Int|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/021_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getInteger(String): Int|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets an integer by key from the dApp's own data storage. .. code-block:: none getInteger(key: String): Int|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/022_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getIntegerValue(Address|Alias, String): Int ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets an integer by key. Fails if there is no data. .. code-block:: none getIntegerValue(addressOrAlias: Address|Alias, key: String): Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/023_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getIntegerValue(String): Int ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets an integer by key from the dApp's own data storage. .. code-block:: none getIntegerValue(key: String): Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/024_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getString(Address|Alias, String): String|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a string by key. .. code-block:: none getString(addressOrAlias: Address|Alias, key: String): String|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/025_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getString(String): String|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a string by key from the dApp's own data storage. .. code-block:: none getString(key: String): String|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/026_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getStringValue(Address|Alias, String): String ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a string by key. Fails if there is no data. .. code-block:: none getStringValue(addressOrAlias: Address|Alias, key: String): String :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/027_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getStringValue(String): String ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a string by key from the dApp's own data storage. .. code-block:: none getString(key: String): String :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/028_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 isDataStorageUntouched(Address|Alias): Boolean ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Checks if the data storage of a given account never contained any entries. Returns false if there was at least one entry in the account data storage even if the entry was deleted. .. code-block:: none isDataStorageUntouched(addressOrAlias: Address|Alias): Boolean :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/029_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let addr = Address(base58'3N4iKL6ikwxiL7yNvWQmw7rg3wGna8uL6LU') isDataStorageUntouched(addr) # Returns false Blockchain Functions -------------------- .. csv-table:: Blockchain Functions :file: ../_static/03_ride-language/tables/030_Blockchain-Functions.csv :header-rows: 1 :class: longtable :widths: 5 4 1 addressFromRecipient(Address|Alias): Address ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets the corresponding :ref:`address <02_decentralchain/01_account:Address>` of the :ref:`alias <02_decentralchain/01_account:Alias>`. .. code-block:: none addressFromRecipient(AddressOrAlias: Address|Alias): Address For a description of the return value, see the :ref:`Address <03_ride-language/05_structures:Address>` structure article. :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/031_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let address = Address(base58'3NADPfTVhGvVvvRZuqQjhSU4trVqYHwnqjF') addressFromRecipient(address) assetBalance(Address|Alias, ByteVector): Int ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets account balance by token ID. .. code-block:: none assetBalance(addressOrAlias: Address|Alias, assetId: ByteVector): Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/032_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 assetInfo(ByteVector): Asset|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets the information about a :ref:`token (asset) <02_decentralchain/02_token(asset):Token (Asset)>`. .. code-block:: none assetInfo(id: ByteVector): Asset|Unit For a description of the return value, see the :ref:`BlockInfo <03_ride-language/05_structures:BlockInfo>` structure article. :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/033_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let bitcoinId = base58'8LQW8f7P5d5PZM7GtZEBgaqRPGSzS3DfPuiXrURJ4AJS' let x = match assetInfo(bitcoinId) { case asset:Asset => asset.decimals # 8 case _ => throw("Can't find asset") } blockInfoByHeight(Int): BlockInfo|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets the information about a :ref:`block <02_decentralchain/04_block:Block>` by the :ref:`block height <02_decentralchain/04_block:Block Height>`. .. code-block:: none blockInfoByHeight(height: Int): BlockInfo|Unit For a description of the return value, see the :ref:`BlockInfo <03_ride-language/05_structures:BlockInfo>` structure article. :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/034_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let x = match blockInfoByHeight(1234567) { case block:BlockInfo => block.generator.toString() # "3P38Z9aMhGKAWnCiyMW4T3PcHcRaTAmTztH" case _ => throw("Can't find block") } calculateAssetId(Issue): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Calculates ID of the token formed by the :ref:`Issue <03_ride-language/05_structures:Issue>` structure when executing the :ref:`callable function <03_ride-language/03_functions:Callable Functions>`. .. code-block:: none calculateAssetId(issue: Issue): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/035_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 4 :strong:`Example` .. code-block:: none {-# STDLIB_VERSION 5 #-} {-# CONTENT_TYPE DAPP #-} {-# SCRIPT_TYPE ACCOUNT #-} @Callable(inv) func issueAndId() = { let issue = Issue("CryptoRouble", "Description", 1000, 2, true) let id = calculateAssetId(issue) ( [ issue, BinaryEntry("id", id) ], unit ) } calculateLeaseId(Lease): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Calculates ID of the lease formed by the :ref:`Lease <03_ride-language/05_structures:Lease>` structure when executing the :ref:`callable function <03_ride-language/03_functions:Callable Functions>`. .. code-block:: none calculateLeaseId(lease: Lease): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/036_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 3 :strong:`Example` .. code-block:: none {-# STDLIB_VERSION 5 #-} {-# CONTENT_TYPE DAPP #-} {-# SCRIPT_TYPE ACCOUNT #-} @Callable(i) func foo() = { let lease = Lease(Alias("merry"),100000000) let id = calculateLeaseId(lease) ( [ lease, BinaryEntry("lease", id) ], unit ) } scriptHash(Address|Alias): ByteVector|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Returns BLAKE2b-256 hash of the script assigned to a given account. Returns unit if there is no script. The function can be used to verify that the script is exactly the same as expected. .. code-block:: none scriptHash(addressOrAlias: Address|Alias): ByteVector|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/037_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let addr = Address(base58'3MxBZbnN8Z8sbYjjL5N3oG5C8nWq9NMeCEm') scriptHash(addr) # Returns base58'G6ihnWN5mMedauCgNa8TDrSKWACPJKGQyYagmMQhPuja' transactionHeightById(ByteVector): Int|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets the :ref:`block height <02_decentralchain/04_block:Block Height>` of a transaction. .. code-block:: none transactionHeightById(id: ByteVector): Int|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/038_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let bitcoinId = base58'8LQW8f7P5d5PZM7GtZEBgaqRPGSzS3DfPuiXrURJ4AJS' let x = match transactionHeightById(bitcoinId) { case h:Int => h # 257457 case _ => throw("Can't find transaction") } transferTransactionById(ByteVector): TransferTransaction|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets the data of a :ref:`transfer transaction <02_decentralchain/03_transaction:Transfer Transaction>`. .. code-block:: none transferTransactionById(id: ByteVector): TransferTransaction|Unit For a description of the return value, see the :ref:`TransferTransaction <03_ride-language/05_structures:TransferTransaction>` structure article. :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/039_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let transferId = base58'J2rcMzCWCZ1P3SFZzvz9PR2NtBjomDh57HTcqptaAJHK' let x = match transferTransactionById(transferId) { case ttx:TransferTransaction => ttx.amount # 3500000000 case _ => throw("Can't find transaction") } decentralchainBalance(Address|Alias): BalanceDetails ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets all types of :ref:`DecentralCoin <02_decentralchain/02_token(asset):DecentralCoin>` balances. For description of balance types, see the :ref:`account balance <02_decentralchain/01_account:Account Balance>` article. .. code-block:: none decentralchainBalance(addressOrAlias: Address|Alias): BalanceDetails :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/040_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 Byte Array Functions -------------------- .. csv-table:: Byte Array Functions :file: ../_static/03_ride-language/tables/041_Byte-Array-Functions.csv :header-rows: 1 :class: longtable :widths: 5 4 1 drop(ByteVector, Int): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Returns the byte array without the first N bytes. .. code-block:: none drop(xs: ByteVector, number: Int): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/042_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none drop("Ride".toBytes(), 2) # Returns the byte array without the first 2 bytes drop(125.toBytes(), 2) # Returns the byte array without the first 2 bytes drop(base16'52696465', 3) # Returns the byte array without the first 3 bytes drop(base58'37BPKA', 3) # Returns the byte array without the first 3 bytes drop(base64'UmlkZQ==', 3) # Returns the byte array without the first 3 bytes dropRight(ByteVector, Int): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Returns the byte array without the last N bytes. .. code-block:: none dropRight(xs: ByteVector, number: Int): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/043_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none dropRight("Ride".toBytes(), 2) # Returns the byte array without the last 2 bytes dropRight(125.toBytes(), 2) # Returns the byte array without the last 2 bytes dropRight(base16'52696465', 3) # Returns the byte array without the last 3 bytes dropRight(base58'37BPKA', 3) # Returns the byte array without the last 3 bytes dropRight(base64'UmlkZQ==', 3) # Returns the byte array without the last 3 bytes size(ByteVector): Int ^^^^^^^^^^^^^^^^^^^^^ Returns the number of bytes in the byte array. .. code-block:: none size(byteVector: ByteVector): Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/044_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none size("Hello".toBytes()) # Returns 5 size("Hello world".toBytes()) # Returns 11 size(64.toBytes()) # Returns 8 because all integers in Ride take 8 bytes size(200000.toBytes()) # Returns 8 because all integers in Ride take 8 bytes size(base58'37BPKA') # Returns 4 take(ByteVector, Int): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Returns the first N bytes of the byte array. .. code-block:: none take(xs: ByteVector, number: Int): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/045_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none take(base58'37BPKA', 0) # Returns the empty byte array take(base58'37BPKA', 1) # Returns the byte array consisting of first byte of initial byte array take(base58'37BPKA', 15) # Returns whole byte array take(base58'37BPKA', -10) # Returns the empty byte array takeRight(ByteVector, Int): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Returns the last N bytes of the byte array. .. code-block:: none takeRight(xs: ByteVector, number: Int): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/046_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none takeRight(base58'37BPKA', 2) # Returns the last 2 bytes of the byte array Converting Functions -------------------- .. csv-table:: Converting Functions :file: ../_static/03_ride-language/tables/047_Converting-Functions.csv :header-rows: 1 :class: longtable :widths: 5 4 1 addressFromPublicKey(ByteVector): Address ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets the corresponding :ref:`address <02_decentralchain/01_account:Address>` of the account public key. .. code-block:: none addressFromPublicKey(publicKey: ByteVector): Address For a description of the return value, see the :ref:`Address <03_ride-language/05_structures:Address>` structure article. :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/048_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let address = addressFromPublicKey(base58'J1t6NBs5Hd588Dn7mAPytqkhgeBshzv3zecScfFJWE2D') parseBigInt(String): BigInt|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Converts the string representation of a number to its :ref:`big integer <03_ride-language/02_data-types:BigInt>` equivalent. .. code-block:: none parseBigInt(str: String): BigInt|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/049_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 parseBigIntValue(String): BigInt ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Converts the string representation of a number to its :ref:`big integer <03_ride-language/02_data-types:BigInt>` equivalent. Fails if the string cannot be parsed. .. code-block:: none parseBigIntValue(str: String): BigInt :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/050_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 parseInt(String): Int|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^ Converts the string representation of a number to its integer equivalent. .. code-block:: none parseInt(str: String): Int|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/051_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none parseInt("10") # Returns 10 parseInt("010") # Returns 10 parseInt("Ride") # Returns Unit parseInt("10.30") # Returns Unit parseIntValue(String): Int ^^^^^^^^^^^^^^^^^^^^^^^^^^ Converts the string representation of a number to its integer equivalent. Fails if the string cannot be parsed. .. code-block:: none parseIntValue(str: String): Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/052_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none parseIntValue("10") # Returns 10 parseIntValue("010") # Returns 10 parseIntValue("Ride") # Error while parsing string to integer parseIntValue("10.30") # Error while parsing string to integer parseIntValue("20 DecentralCoins") # Error while parsing string to integer toBigInt(ByteVector): BigInt ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Converts an array of bytes to a :ref:`big integer <03_ride-language/02_data-types:BigInt>` using the big-endian byte order. .. code-block:: none toBigInt(bin: ByteVector): BigInt :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/053_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 toBigInt(ByteVector, Int, Int): BigInt ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Converts an array of bytes starting from a certain index to a :ref:`big integer <03_ride-language/02_data-types:BigInt>` using the big-endian byte order. .. code-block:: none toBigInt(bin: ByteVector, offset: Int, size: Int): BigInt :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/054_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 3 toBigInt(Int): BigInt ^^^^^^^^^^^^^^^^^^^^^ Converts an integer to a :ref:`big integer <03_ride-language/02_data-types:BigInt>`. .. code-block:: none toBigInt(n: Int): BigInt :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/055_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 toBytes(Boolean): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Converts a boolean value to an array of bytes. .. code-block:: none toBytes(b: Boolean): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/056_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none toBytes(true) # Returns base58'2' toBytes(false) # Returns base58'1' toBytes(Int): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^ Converts an integer to an array of bytes using the big-endian byte order. .. code-block:: none toBytes(n: Int): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/057_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none toBytes(10) # Returns base58'1111111B' toBytes(String): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Converts a string to an array of bytes. .. code-block:: none toBytes(s: String): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/058_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none toBytes("Ride") # Returns base58'37BPKA' toBytes(BigInt): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Converts a :ref:`big integer <03_ride-language/02_data-types:BigInt>` to an array of bytes using the big-endian byte order. .. code-block:: none toBytes(n: BigInt): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/059_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 toInt(BigInt): Int ^^^^^^^^^^^^^^^^^^ Converts a :ref:`big integer <03_ride-language/02_data-types:BigInt>` to an integer. Fails if the number cannot be converted. .. code-block:: none toInt(n: BigInt): Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/060_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 toInt(ByteVector): Int ^^^^^^^^^^^^^^^^^^^^^^ Converts an array of bytes to an integer using the big-endian byte order. .. code-block:: none toInt(bin: ByteVector) : Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/061_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none toInt(base58'1111111B') # Returns 10 toInt(ByteVector, Int): Int ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Converts an array of bytes to an integer starting from a certain index using the big-endian byte order. .. code-block:: none toInt(bin: ByteVector, offset: Int): Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/062_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let bytes = toBytes("Ride") toInt(bytes, 2) # Returns 7234224039401641825 toInt(bytes, 6) # Index out of bounds toString(Address): String ^^^^^^^^^^^^^^^^^^^^^^^^^ Converts an array of bytes of an :ref:`address <02_decentralchain/01_account:Address>` to a string. .. code-block:: none toString(addr: Address): String :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/063_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let address = Address(base58'3NADPfTVhGvVvvRZuqQjhSU4trVqYHwnqjF') toString(address) # Returns "3NADPfTVhGvVvvRZuqQjhSU4trVqYHwnqjF" toString(Boolean): String ^^^^^^^^^^^^^^^^^^^^^^^^^ Converts a boolean value to a string. .. code-block:: none toString(b: Boolean): String :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/064_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none toString(true) # Returns "true" toString(false) # Returns "false" toString(Int): String ^^^^^^^^^^^^^^^^^^^^^ Converts an integer to a string. .. code-block:: none toString(n: Int): String :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/065_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none toString(10) # Returns "10" toString(BigInt): String ^^^^^^^^^^^^^^^^^^^^^^^^ Converts a :ref:`big integer <03_ride-language/02_data-types:BigInt>` to a string. .. code-block:: none toString(n: BigInt): String :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/066_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 toUtf8String(ByteVector): String ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Converts an array of bytes to a UTF-8 string. Fails if the array of bytes cotains an invalid UTF-8 sequence. .. code-block:: none toUtf8String(u: ByteVector): String :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/067_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let bytes = toBytes("Ride") toUtf8String(bytes) # Returns "Ride" transferTransactionFromProto(ByteVector): TransferTransaction|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Deserializes transfer transaction: converts protobuf-encoded :ref:`binary format <02_decentralchain/10_binary-format:Transfer Transaction Binary Format>` specified in transaction.proto to a TransferTransaction structure. Returns unit if deserialization failed. .. code-block:: none transferTransactionFromProto(b: ByteVector): TransferTransaction|Unit For a description of the return value, see the :ref:`TransferTransaction <03_ride-language/05_structures:TransferTransaction>` structure article. :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/068_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 4 :strong:`Example` .. code-block:: none let transfer = base64'Cr4BCFQSIA7SdnwUqEBY+k4jUf9sCV5+xj0Ry/GYuwmDMCdKTdl3GgQQoI0GIPLIyqL6LSgDwgaHAQoWChT+/s+ZWeOWzh1eRnhdRL3Qh9bxGRIkCiBO/wEBhwH/f/+bAWBRMv+A2yiAOUeBc9rY+UR/a4DxKBBkGkcaRYCcAQAB//9/AX9//0695P8EiICAfxgBgIkefwHYuDmA//83/4ABJgEBAf8d9N+8AAERyo1/j3kAGn/SAb7YIH8y/4CAXg==' let x = match transferTransactionFromProto(transfer) { case ttx:TransferTransaction => ttx.amount # 3500000000 case _ => throw("Can't find transaction") } dApp-to-dApp Invocation Functions --------------------------------- .. csv-table:: dApp-to-dApp Invocation Functions :file: ../_static/03_ride-language/tables/069_dApp-to-dApp-Invocation-Functions.csv :header-rows: 1 :class: longtable :widths: 5 4 1 invoke(Address|Alias, String, List[Any], List[AttachedPayments]): Any ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Invokes a dApp :ref:`callable function <03_ride-language/03_functions:Callable Functions>`, with reentrancy restriction. .. code-block:: none invoke(dApp: Address|Alias, function: String, arguments: List[Any], payments: List[AttachedPayments]): Any Any means any valid type. You can extract a particular type from it using as[T] and exactAs[T] macros or the match ... case operator, see the :ref:`any <03_ride-language/02_data-types:Any>` article. The invoke function can be used by a callable function of a :ref:`dApp script <03_ride-language/04_script-types:dApp Script>`, but not by a verifier function, :ref:`account script <03_ride-language/04_script-types:Account Script>` or :ref:`asset script <03_ride-language/04_script-types:Asset Script>`. Via the invoke function, the callable function can invoke a callable function of another dApp, or another callable function of the same dApp, or even itself, and then use the invocation results in subsequent operations. For details, see the :ref:`dApp-to-dApp invocation <03_ride-language/07_dapp-to-app-invocation:dApp-to-App Invocation>` article. To ensure executing callable functions and applying their actions in the right order, initialize a :ref:`strict variable <03_ride-language/01_syntax-basics:Strict Variables>` by the return value of an invoke function. The invocation can contain payments that will be transferred from the balance of the parent dApp to the balance of the invoked dApp. Payments are forbidden if the dApp invokes itself. If a payment token is a smart asset, the asset script verifies the invoke as if it was :ref:`InvokeScriptTransaction <03_ride-language/05_structures:InvokeScriptTransaction>` structure with the following fields: * DApp, payments, function, args indicated in the invoke function. * Sender, senderPublicKey of the dApp that performs the invocation. * Id, timestamp, fee, feeAssetId indicated in the original invoke script transaction. * Version = 0; If the asset script denies the action, the Invoke Script transaction is either discarded or saved on the blockchain as failed, see the :ref:`transaction validation <02_decentralchain/03_transaction:Transaction Validation>` article. :strong:`Reentrancy Restriction` The invocation stack generated by the invoke function must not contain invocations of the parent dApp after invocation of another dApp. Let the parent dApp A invokes dApp B using the invoke function. Regardless of whether dApp B uses invoke or reentrantInvoke, the following invocation stacks will fail: .. code-block:: none → dApp A → dapp B → dApp A .. code-block:: none → dApp A → dapp B → dApp C → dApp A The following invocation stacks are valid: .. code-block:: none → dApp A → dapp A → dapp A .. code-block:: none → dApp N → dapp A → dApp A .. code-block:: none → dapp N → dapp A → dapp B → dapp B → dapp A → dapp C .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/070_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` A user sends an invoke script transaction that invokes the callable function foo of dApp1. The foo function invokes the bar function of dApp2 passing the number a and attaching a payment of 1 USDN. The bar function transfers :math:`1` :ref:`DecentralCoin <02_decentralchain/02_token(asset):DecentralCoin>` to dApp1 and returns the doubled number a. The foo function writes to dApp1 data storage: * The value returned by bar. * The new balance of dApp2 (reduced by :math:`1` DecentralCoin transferred to dApp1). dApp1: .. code-block:: none {-# STDLIB_VERSION 5 #-} {-# CONTENT_TYPE DAPP #-} {-# SCRIPT_TYPE ACCOUNT #-} @Callable(i) func foo(dapp2: String, a: Int, key1: String, key2: String) = { strict res = invoke(addressFromStringValue(dapp2),"bar",[a],[AttachedPayment(base58'DG2xFkPdDwKUoBkzGAhQtLpSGzfXLiCYPEzeKH2Ad24p',1000000)]) match res { case r : Int => ( [ IntegerEntry(key1, r), IntegerEntry(key2, decentralchainBalance(addressFromStringValue(dapp2)).regular) ], unit ) case _ => throw("Incorrect invoke result") } } dApp2: .. code-block:: none {-# STDLIB_VERSION 5 #-} {-# CONTENT_TYPE DAPP #-} {-# SCRIPT_TYPE ACCOUNT #-} @Callable(i) func bar(a: Int) = { ( [ ScriptTransfer(i.caller, 100000000, unit) ], a*2 ) } reentrantInvoke(Address|Alias, String, List[Any], List[AttachedPayments]): Any ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Invokes a dApp :ref:`callable function <03_ride-language/03_functions:Callable Functions>`. The only difference from the invoke function above is that there is no reentrancy restriction for the parent dApp that uses reentrantInvoke. However, if the parent dApp is invoked again and this time uses the invoke function, the parent dApp cannot be invoked again in this invocation stack. For example, the invocation stack: .. code-block:: none → dApp A → dapp B → dApp A → dApp C → dApp A * Is valid if dApp A invokes both dApp B and dApp C via the reentrantInvoke function; * Fails if dApp A invokes dApp B via the reentrantInvoke function and invokes dApp C via the invoke function. .. code-block:: none reentrantInvoke(dApp: Address|Alias, function: String, arguments: List[Any], payments: List[AttachedPayments]): Any Data Transaction Functions -------------------------- The functions listed below retrieve data by key from the :ref:`DataTransaction <03_ride-language/05_structures:DataTransaction>` structure or from any list of data entries. .. csv-table:: Data Transaction Functions :file: ../_static/03_ride-language/tables/071_Data-Transaction-Functions.csv :header-rows: 1 :class: longtable :widths: 5 4 1 getBinary(List[], String): ByteVector|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a binary value from a list of data entires by key. .. code-block:: none getBinary(data: List[BinaryEntry|BooleanEntry|IntegerEntry|StringEntry], key: String): ByteVector|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/072_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getBinary(List[], Int): ByteVector|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a binary value from a list of data entires by index. .. code-block:: none getBinary(data: List[BinaryEntry|BooleanEntry|IntegerEntry|StringEntry], index: Int): ByteVector|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/073_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getBinaryValue(List[], String): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a binary value from a list of data entires by key. Fails if there is no data. .. code-block:: none getBinaryValue(data: List[BinaryEntry|BooleanEntry|IntegerEntry|StringEntry], key: String): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/074_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getBinaryValue(List[], Int): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a binary value from a list of data entires by index. Fails if there is no data. .. code-block:: none getBinaryValue(data: List[BinaryEntry|BooleanEntry|IntegerEntry|StringEntry], index: Int): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/075_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getBoolean(List[], String): Boolean|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a boolean value from a list of data entires by key. .. code-block:: none getBoolean(data: List[BinaryEntry|BooleanEntry|IntegerEntry|StringEntry], key: String): Boolean|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/076_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getBoolean(List[], Int): Boolean|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a boolean value from a list of data entires by index. .. code-block:: none getBoolean(data: List[BinaryEntry|BooleanEntry|IntegerEntry|StringEntry], index: Int): Boolean|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/077_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getBooleanValue(List[], String): Boolean ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a boolean value from a list of data entires by key. Fails if there is no data. .. code-block:: none getBooleanValue(data: List[BinaryEntry|BooleanEntry|IntegerEntry|StringEntry], key: String): Boolean :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/078_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getBooleanValue(List[], Int): Boolean ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a boolean value from a list of data entires by index. Fails if there is no data. .. code-block:: none getBooleanValue(data: List[BinaryEntry|BooleanEntry|IntegerEntry|StringEntry], index: Int): Boolean :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/079_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getInteger(List[], String): Int|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets integer from a list of data entires by key. .. code-block:: none getInteger(data: List[BinaryEntry|BooleanEntry|IntegerEntry|StringEntry], key: String): Int|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/080_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getInteger(List[], Int): Int|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets an integer value from a list of data entires by index. .. code-block:: none getInteger(data: List[BinaryEntry|BooleanEntry|IntegerEntry|StringEntry], index: Int): Int|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/081_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getIntegerValue(List[], String): Int ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets an integer value from a list of data entires by key. Fails if there is no data. .. code-block:: none getIntegerValue(data: List[BinaryEntry|BooleanEntry|IntegerEntry|StringEntry], key: String): Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/082_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getIntegerValue(List[], Int): Int ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets an integer value from a list of data entires by index. Fails if there is no data. .. code-block:: none getIntegerValue(data: List[BinaryEntry|BooleanEntry|IntegerEntry|StringEntry], index: Int): Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/083_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getString(List[], String): String|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a string value from a list of data entires by key. .. code-block:: none getString(data: List[BinaryEntry|BooleanEntry|IntegerEntry|StringEntry], key: String): String|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/084_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getString(List[], Int): String|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a string value from a list of data entires by key. .. code-block:: none getString(data: List[BinaryEntry|BooleanEntry|IntegerEntry|StringEntry], index: Int): String|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/085_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getStringValue(List[], String): String ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a string value from a list of data entires by key. Fails if there is no data. .. code-block:: none getStringValue(data: List[BinaryEntry|BooleanEntry|IntegerEntry|StringEntry], key: String): String :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/086_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getStringValue(List[], Int): String ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets a string value from a list of data entires by index. Fails if there is no data. .. code-block:: none getStringValue(data: List[BinaryEntry|BooleanEntry|IntegerEntry|StringEntry], index: Int): String :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/087_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 Decoding Functions ------------------ .. csv-table:: Decoding Functions :file: ../_static/03_ride-language/tables/088_Decoding-Functions.csv :header-rows: 1 :class: longtable :widths: 5 4 1 addressFromString(String): Address|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Decodes address from base58 string. .. code-block:: none addressFromString(string: String): Address|Unit For a description of the return value, see the :ref:`Address <03_ride-language/05_structures:Address>` structure article. :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/089_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let address = addressFromString("3NADPfTVhGvVvvRZuqQjhSU4trVqYHwnqjF") addressFromStringValue(String): Address ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Decodes address from base58 string. Fails if the address cannot be decoded. .. code-block:: none addressFromStringValue(string: String): Address For a description of the return value, see the :ref:`Address <03_ride-language/05_structures:Address>` structure article. :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/090_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let address = addressFromStringValue("3NADPfTVhGvVvvRZuqQjhSU4trVqYHwnqjF") fromBase16String(String): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Decodes a base16 string to an array of bytes. .. code-block:: none fromBase16String(str: String): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/091_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let bytes = fromBase16String("52696465") fromBase58String(String): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Decodes a base58 string to an array of bytes. .. code-block:: none fromBase58String(str: String): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/092_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let bytes = fromBase58String("37BPKA") fromBase64String(String): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Decodes a base64 string to an array of bytes. .. code-block:: none fromBase64String(str: String): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/093_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let bytes = fromBase64String("UmlkZQ==") Encoding Functions ------------------ .. csv-table:: Encoding Functions :file: ../_static/03_ride-language/tables/094_Encoding-Functions.csv :header-rows: 1 :class: longtable :widths: 5 4 1 toBase16String(ByteVector): String ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Encodes an array of bytes to a base16 string. .. code-block:: none toBase16String(bytes: ByteVector): String :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/095_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none toBase16String("Ride".toBytes()) # Returns "52696465" toBase16String(base16'52696465') # Returns "52696465" toBase58String(ByteVector): String ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Encodes an array of bytes to a base58 string. .. code-block:: none toBase58String(bytes: ByteVector): String :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/096_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none toBase58String("Ride".toBytes()) # Returns "37BPKA" toBase58String(base58'37BPKA') # Returns "37BPKA toBase64String(ByteVector): String ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Encodes an array of bytes to a base64 string. .. code-block:: none toBase64String(bytes: ByteVector): String :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/097_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none toBase64String("Ride".toBytes()) # Returns "UmlkZQ==" toBase64String(base64'UmlkZQ==') # Returns "UmlkZQ==" Exception Functions ------------------- .. csv-table:: Exception Functions :file: ../_static/03_ride-language/tables/098_Exception-Functions.csv :header-rows: 1 :class: longtable :widths: 5 4 1 The return type of throw is nothing. There is no exception handling in Ride: after an exception has been thrown, the script execution fails. The transaction can be either discarded or saved on the blockchain as failed, see the :ref:`transaction validation <02_decentralchain/03_transaction:Transaction Validation>` article for details. throw() ^^^^^^^ Raises an exception. throw(String) ^^^^^^^^^^^^^ Raises an exception with a message. .. code-block:: none throw(err: String) :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/099_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 Hashing Functions ----------------- .. csv-table:: Hashing Functions :file: ../_static/03_ride-language/tables/100_Hashing-Functions.csv :header-rows: 1 :class: longtable :widths: 5 4 1 blake2b256(ByteVector): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Range of functions that hash an array of bytes using BLAKE2b-256. .. csv-table:: blake2b256 :file: ../_static/03_ride-language/tables/101_blake2b256.csv :header-rows: 1 :class: longtable :widths: 4 1 1 :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/102_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 4 :strong:`Example` .. code-block:: none blake2b256("Ride".toBytes()) # Returns 6NSWRz5XthhFVm9uVQHuisdaseQJfc4WMGajN435v3f4 blake2b256(125.toBytes())  # Returns H9emWhyMuyyjDmNkgx7jAfHRuy9icXK3uYJuVw6R1uuK blake2b256(base16'52696465') # Returns 6NSWRz5XthhFVm9uVQHuisdaseQJfc4WMGajN435v3f4 blake2b256(base58'37BPKA')  # Returns 6NSWRz5XthhFVm9uVQHuisdaseQJfc4WMGajN435v3f4 blake2b256(base64'UmlkZQ==') # Returns 6NSWRz5XthhFVm9uVQHuisdaseQJfc4WMGajN435v3f4 keccak256(ByteVector): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Range of functions that hash an array of bytes using Keccak-256. .. csv-table:: keccak256 :file: ../_static/03_ride-language/tables/103_keccak256.csv :header-rows: 1 :class: longtable :widths: 4 1 1 :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/104_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 4 :strong:`Example` .. code-block:: none keccak256("Ride".toBytes()) # Returns 4qa5wNk4961VwJAjCKBzXiEvBQ2gBJoqDcLFRJTiSKpv keccak256(125.toBytes())  # Returns 5UUkcH6Fp2E3mk7NSqSTs3JBP33zL3SB3yg4b2sR5gpF keccak256(base16'52696465') # Returns 4qa5wNk4961VwJAjCKBzXiEvBQ2gBJoqDcLFRJTiSKpv keccak256(base58'37BPKA')  # Returns 4qa5wNk4961VwJAjCKBzXiEvBQ2gBJoqDcLFRJTiSKpv keccak256(base64'UmlkZQ==') # Returns 4qa5wNk4961VwJAjCKBzXiEvBQ2gBJoqDcLFRJTiSKpv sha256(ByteVector): ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Range of functions that hash an array of bytes using SHA-256. .. csv-table:: sha256 :file: ../_static/03_ride-language/tables/105_sha256.csv :header-rows: 1 :class: longtable :widths: 4 1 1 :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/106_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 4 :strong:`Example` .. code-block:: none sha256("Ride".toBytes()) # Returns 5YxvrKsjJtq4G325gRVxbXpkox1sWdHUGVJLnRFqTWD3 sha256(125.toBytes())  # Returns A56kbJjy7A4B9Pa5tUgRNvtCHSsZ7pZVJuPsLT2vtPSU sha256(base16'52696465') # Returns 5YxvrKsjJtq4G325gRVxbXpkox1sWdHUGVJLnRFqTWD3 sha256(base58'37BPKA')  # Returns 5YxvrKsjJtq4G325gRVxbXpkox1sWdHUGVJLnRFqTWD3 sha256(base64'UmlkZQ==') # Returns 5YxvrKsjJtq4G325gRVxbXpkox1sWdHUGVJLnRFqTWD3 List Functions -------------- .. csv-table:: List Functions :file: ../_static/03_ride-language/tables/107_List-Functions.csv :header-rows: 1 :class: longtable :widths: 5 4 1 A, B, T means any valid type. cons(A, List[B]): List[A|B] ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Inserts element to the beginning of the :ref:`list <03_ride-language/02_data-types:List>`. .. code-block:: none cons(head:T, tail: List[T]): List[T] :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/108_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none cons("Hello", ["World", "."]) # Returns ["Hello", "World", "."] cons(1, [2, 3, 4, 5]) # Returns [1, 2, 3, 4, 5] containsElement(List[T], T): Boolean ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Check if the element is in the :ref:`list <03_ride-language/02_data-types:List>`. .. code-block:: none containsElement(list: List[T], element: T): Boolean :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/109_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 getElement(List[T], Int): T ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Gets the element from the :ref:`list <03_ride-language/02_data-types:List>` by index. .. code-block:: none getElement(arr: List[T], pos: Int): T :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/110_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none getElement(["Hello", "World", "."], 0) # Returns "Hello" getElement([false, true], 1) # Returns true indexOf(List[T], T): Int|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Returns the index of the first occurrence of the element in the :ref:`list <03_ride-language/02_data-types:List>` or unit if the element is missing. .. code-block:: none indexOf(list: List[T], element: T): Int|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/111_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let stringList = ["a","b","a","c"] indexOf("a", stringList) # Returns 0 lastIndexOf(List[T], T): Int|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Returns the index of the last occurrence of the element in the :ref:`list <03_ride-language/02_data-types:List>` or unit if the element is missing. .. code-block:: none lastIndexOf(list: List[T], element: T): Int|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/112_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none let stringList = ["a","b","a","c"] lastIndexOf("a", stringList) # Returns 2 max(List[Int]): Int ^^^^^^^^^^^^^^^^^^^ Returns the largest element in the :ref:`list <03_ride-language/02_data-types:List>` of integers. Fails if the list is empty. .. code-block:: none max(List[Int]): Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/113_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 max(List[BigInt]): BigInt ^^^^^^^^^^^^^^^^^^^^^^^^^ Returns the largest element in the list of :ref:`big integers <03_ride-language/02_data-types:BigInt>`. Fails if the list is empty. .. code-block:: none max(List[BigInt]): BigInt :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/114_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 min(List[Int]): Int ^^^^^^^^^^^^^^^^^^^ Returns the smallest element in the :ref:`list <03_ride-language/02_data-types:List>` of integers. Fails if the list is empty. .. code-block:: none min(List[Int]): Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/115_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 min(List[BigInt]): BigInt ^^^^^^^^^^^^^^^^^^^^^^^^^ Returns the smallest element in the list of :ref:`big integers <03_ride-language/02_data-types:BigInt>`. Fails if the list is empty. .. code-block:: none min(List[BigInt]): BigInt :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/116_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 removeByIndex(List[T], Int): List[T] ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Removes an element from the :ref:`list <03_ride-language/02_data-types:List>` by index. .. code-block:: none removeByIndex(list: List[T], index: Int): List[T] :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/117_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none removeByIndex(["Ride", 42, true], 1) # Returns ["Ride", true] size(List[T]): Int ^^^^^^^^^^^^^^^^^^ Returns the size of the :ref:`list <03_ride-language/02_data-types:List>`. .. code-block:: none size(arr: List[T]): Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/118_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none size(["Hello", "World", "."]) # Returns 3 Math Functions -------------- .. csv-table:: Math Functions :file: ../_static/03_ride-language/tables/119_Math-Functions.csv :header-rows: 1 :class: longtable :widths: 5 4 1 fraction(Int, Int, Int): Int ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Multiplies :ref:`integers <03_ride-language/02_data-types:Int>` :math:`a`, :math:`b` and divides the result by the integer :math:`c` to avoid overflow. Fraction :math:`a × b / c` should not exceed the maximum value of the integer type :math:`9,223,372,036,854,755,807`. The rounding method is DOWN, see rounding variables below. .. code-block:: none fraction(a: Int, b: Int, c: Int): Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/120_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` Lets assume that: :math:`a = 100,000,000,000`, :math:`b = 50,000,000,000,000`, :math:`c = 2,500,000`. The following formula, with :ref:`operators <03_ride-language/01_syntax-basics:Operators>` \* and /, fails due to overflow: .. code-block:: none a * b / c # overflow, because a × b exceeds max integer value The fraction function with no overflow: .. code-block:: none fraction(a, b, c) # Result: 2,000,000,000,000,000,000 fraction(Int, Int, Int, Union): Int ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Multiplies :ref:`integers <03_ride-language/02_data-types:Int>` :math:`a`, :math:`b` and divides the result by the integer :math:`c` to avoid overflow, applying the specified rounding method. Fraction :math:`a × b / c` should not exceed the maximum value of the integer type :math:`9,223,372,036,854,755,807`. .. code-block:: none fraction(a: Int, b: Int, c: Int, round: DOWN|CEILING|FLOOR|HALFUP|HALFEVEN): Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/121_Parameters.csv :header-rows: 1 :class: longtable :widths: 2 1 fraction(BigInt, BigInt, BigInt): BigInt ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Multiplies :ref:`integers <03_ride-language/02_data-types:Int>` :math:`a`, :math:`b` and divides the result by the integer :math:`c` to avoid overflow, applying the specified rounding method. Fraction :math:`a × b / c` should not exceed the maximum value of the integer type :math:`9,223,372,036,854,755,807`. .. code-block:: none fraction(a: BigInt, b: BigInt, c: BigInt): BigInt :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/122_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 fraction(BigInt, BigInt, BigInt, Union): BigInt ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Multiplies :ref:`integers <03_ride-language/02_data-types:Int>` :math:`a`, :math:`b` and divides the result by the integer :math:`c` to avoid overflow, applying the specified rounding method. Fraction :math:`a × b / c` should not exceed the maximum value of the integer type :math:`9,223,372,036,854,755,807`. .. code-block:: none fraction(a: BigInt, b: BigInt, c: BigInt, round: DOWN|CEILING|FLOOR|HALFUP|HALFEVEN): BigInt :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/123_Parameters.csv :header-rows: 1 :class: longtable :widths: 2 1 log(Int, Int, Int, Int, Int, Union): Int ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Calculates :math:`\log_b a`. .. code-block:: none log(value: Int, vp: Int, base: Int, bp: Int, rp: Int, round: DOWN|CEILING|FLOOR|HALFUP|HALFEVEN): Int In Ride, there is no :ref:`data type <03_ride-language/02_data-types:Data Types>` with the floating point. That is why, for example, when you need to calculate :math:`\log_{2.7} 16.25` then the number value :math:`= 1625`, vp :math:`= 2` and the base :math:`= 27`, bp :math:`= 1`. If the log function returns, for example, :math:`2807035420964590265`, and the parameter rp :math:`= 18`, then the result is :math:`2.807035420964590265`; in the number :math:`2807035420964590265` the last :math:`18` digits is a fractional part. :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/124_Parameters.csv :header-rows: 1 :class: longtable :widths: 2 1 :strong:`Example` :math:`\log_{2.7} 16.25 = 2.807035421...` .. code-block:: none log(1625, 2, 27, 1, 2, HALFUP) # Function returns 281, so the result is: 2.81 log(1625, 2, 27, 1, 5, HALFUP) # Function returns 280703542, so the result is: 2.80704 log(0, 0, 2, 0, 0, HALFUP) # Result: -Infinity log(BigInt, Int, BigInt, Int, Int, Union): BigInt ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Calculates :math:`\log_b a` with high accuracy. .. code-block:: none log(value: BigInt, ep: Int, base: BigInt, bp: Int, rp: Int, round: DOWN|CEILING|FLOOR|HALFUP|HALFEVEN): BigInt :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/125_Parameters.csv :header-rows: 1 :class: longtable :widths: 2 1 median(List[Int]): Int ^^^^^^^^^^^^^^^^^^^^^^ Returns the median of the :ref:`list <03_ride-language/02_data-types:List>` of integers. Fails if the list is empty. .. code-block:: none median(arr: List[Int]): Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/126_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none median([1, 2, 3]) # Returns 2 median([2, 4, 9, 20]) # Returns 6 median([-2, -4, -9, -20]) # Returns -7 median(List[BigInt]): BigInt ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Returns the median of a :ref:`list <03_ride-language/02_data-types:List>` of :ref:`big integers <03_ride-language/02_data-types:BigInt>`. Fails if the list is empty or contains more than :math:`100` elements. .. code-block:: none median(arr: List[BigInt]): BigInt :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/127_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 pow(Int, Int, Int, Int, Int, Union): Int ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Calculates :math:`a^{b}`. .. code-block:: none pow(base: Int, bp: Int, exponent: Int, ep: Int, rp: Int, round: DOWN|CEILING|FLOOR|HALFUP|HALFEVEN): Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/128_Parameters.csv :header-rows: 1 :class: longtable :widths: 2 1 :strong:`Example` :math:`16.25^{2.7} = 1859,1057168...` .. code-block:: none pow(1625, 2, 27, 1, 2, HALFUP) # function returns 185911, so the result is: 1859.11 pow(1625, 2, 27, 1, 5, HALFUP) # function returns 185910572, so, the result is: 1859.10572 pow(BigInt, Int, BigInt, Int, Int, Union): BigInt ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Calculates :math:`a^{b}` with high accuracy. .. code-block:: none pow(base: BigInt, bp: Int, exponent: BigInt, ep: Int, rp: Int, round: DOWN|CEILING|FLOOR|HALFUP|HALFEVEN): BigInt :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/129_Parameters.csv :header-rows: 1 :class: longtable :widths: 2 1 Rounding Variables ^^^^^^^^^^^^^^^^^^ Below is the list of built-in rounding variables. The rounding variables are only used as the parameters of functions fraction, log, pow. :strong:`Parameters` .. csv-table:: Rounding Variables :file: ../_static/03_ride-language/tables/130_Rounding-Variables.csv :header-rows: 1 :class: longtable :widths: 1 3 :strong:`Example` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/131_Example.csv :header-rows: 1 :class: longtable :widths: 3 1 1 1 1 1 String Functions ---------------- .. csv-table:: String Functions :file: ../_static/03_ride-language/tables/132_String-Functions.csv :header-rows: 1 :class: longtable :widths: 5 4 1 contains(String, String): Boolean ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Checks whether the string contains substring. .. code-block:: none contains(haystack: String, needle: String): Boolean :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/133_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none "hello".contains("hell") # Returns true "hello".contains("world") # Returns false drop(String, Int): String ^^^^^^^^^^^^^^^^^^^^^^^^^ Drops the first n characters of a string. .. code-block:: none drop(xs: String, number: Int): String :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/134_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none drop("Apple", 0) # Returns "Apple" drop("Apple", 1) # Returns "pple" drop("Apple", 3) # Returns "le" drop("Apple", 5) # Returns an empty string drop("Apple", 15) # Returns an empty string dropRight(String, Int): String ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Drops the last n characters of a string. .. code-block:: none dropRight(xs: String, number: Int): String :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/135_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none dropRight("Apple", 0) # Returns "Apple" dropRight("Apple", 1) # Returns "Appl" dropRight("Apple", 3) # Returns "Ap" dropRight("Apple", 5) # Returns an empty string dropRight("Apple", 15) # Returns an empty string indexOf(String, String): Int|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Returns the index of the first occurrence of a substring. .. code-block:: none indexOf(str: String, substr: String): Int|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/136_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none indexOf("Apple","ple") # Returns 3 indexOf("Apple","le") # Returns 4 indexOf("Apple","e") # Returns 5 indexOf(String, String, Int): Int|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Returns the index of the first occurrence of a substring after a certain index. .. code-block:: none indexOf(str: String, substr: String, offset: Int): Int|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/137_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none indexOf("Apple","ple", 1) # Returns 2 indexOf("Apple","le", 2) # Returns 3 indexOf("Apple","e", 3) # Returns 4 lastIndexOf(String, String): Int|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Returns the index of the last occurrence of a substring. .. code-block:: none lastIndexOf(str: String, substr: String): Int|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/138_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none lastIndexOf("Apple","pp") # Returns 1 lastIndexOf("Apple","p") # Returns 2 lastIndexOf("Apple","s") # Returns unit lastIndexOf(String, String, Int): Int|Unit ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Returns the index of the last occurrence of a substring before a certain index. .. code-block:: none lastIndexOf(str: String, substr: String, offset: Int): Int|Unit :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/139_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none lastIndexOf("mamamama","ma",4) # Returns 4 lastIndexOf("mamamama","ma",3) # Returns 2 makeString(List[String], String): String ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Concatenates list strings adding a separator. .. code-block:: none makeString(arr: List[String], separator: String): String :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/140_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none makeString(["Apple","Orange","Mango"], " & ") # Returns "Apple & Orange & Mango" size(String): Int ^^^^^^^^^^^^^^^^^ Returns the size of a string. .. code-block:: none size(xs: String): Int :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/141_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none size("Ap") # Returns 2 size("Appl") # Returns 4 size("Apple") # Returns 5 split(String, String): List[String] ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Splits a string delimited by a separator into a list of substrings. .. code-block:: none split(str: String, separator: String): List[String] :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/142_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none split("A.p.p.l.e", ".") # Returns ["A", "p", "p", "l", "e"] split("Apple", ".") # Returns ["Apple"] split("Apple", "") # Returns ["A", "p", "p", "l", "e"] split("Ap.ple", ".") # Returns ["Ap","ple"] take(String, Int): String ^^^^^^^^^^^^^^^^^^^^^^^^^ Takes the first n characters from a string. .. code-block:: none take(xs: String, number: Int): String :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/143_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none take("Apple", 0) # Returns an empty string take("Apple", 1) # Returns "A" take("Apple", 3) # Returns "App" take("Apple", 5) # Returns "Apple" take("Apple", 15) # Returns "Apple" take("Apple", -10) # Returns an empty string takeRight(String, Int): String ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Takes the last n characters from a string. .. code-block:: none takeRight(xs: String, number: Int): String :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/144_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none takeRight("Apple", 0) # Returns an empty string takeRight("Apple", 1) # Returns "A" takeRight("Apple", 3) # Returns "ple" takeRight("Apple", 5) # Returns "Apple" takeRight("Apple", 15) # Returns "Apple" Union Functions --------------- .. csv-table:: Union Functions :file: ../_static/03_ride-language/tables/145_Union-Functions.csv :header-rows: 1 :class: longtable :widths: 5 4 1 isDefined(T|Unit): Boolean ^^^^^^^^^^^^^^^^^^^^^^^^^^ Checks if an argument is not unit. .. code-block:: none isDefined(a: T|Unit): Boolean :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/146_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 value(T|Unit): T ^^^^^^^^^^^^^^^^ Gets a value from a :ref:`union <03_ride-language/02_data-types:Union>` type argument. Fails if it is :ref:`unit <03_ride-language/02_data-types:Unit>`. .. code-block:: none value(a: T|Unit): T :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/147_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 valueOrElse(T|Unit, T): T ^^^^^^^^^^^^^^^^^^^^^^^^^ Returns a value from a :ref:`union <03_ride-language/02_data-types:Union>` type argument if it's not :ref:`unit <03_ride-language/02_data-types:Unit>`. Otherwise, returns the second argument. .. code-block:: none valueOrElse(t: T|Unit, t0: T): T :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/148_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 valueOrErrorMessage(T|Unit, String): T ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Returns a value from a :ref:`union <03_ride-language/02_data-types:Union>` type argument if it's not :ref:`unit <03_ride-language/02_data-types:Unit>`. Otherwise, fails with the message specified in the second argument. .. code-block:: none valueOrErrorMessage(a: T|Unit, msg: String): T :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/149_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 Verification Functions ---------------------- .. csv-table:: Verification Functions :file: ../_static/03_ride-language/tables/150_Verification-Functions.csv :header-rows: 1 :class: longtable :widths: 5 4 1 bn256groth16Verify(ByteVector, ByteVector, ByteVector): Boolean ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Range of functions. Check zk-SNARK by groth16 protocol on the bn254 curve. (Although the curve is called bn254 in the scientific literature, it is commonly referred to as bn256 in the code.) .. csv-table:: bn256groth16Verify :file: ../_static/03_ride-language/tables/151_bn256groth16Verify.csv :header-rows: 1 :class: longtable :widths: 5 1 1 :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/152_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 createMerkleRoot(List[ByteVector], ByteVector, Int) : ByteVector ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Calculates the Merkle root hash for transactions of block on the basis of the transaction hash and the sibling hashes of the Merkle tree. BLAKE2b-256 algorithm is used for hashing. To check for the transaction in the block, you need to compare the calculated hash with the transactionsRoot field in the block header. For more informtion see the :ref:`transactions root hash <02_decentralchain/04_block:Transactions Root Hash>`. .. code-block:: none createMerkleRoot(merkleProofs: List[ByteVector], valueBytes: ByteVector, index: Int): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/153_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 ecrecover(messageHash: ByteVector, signature: ByteVector) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Recovers public key from the message hash and the ECDSA digital signature based on the secp256k1 elliptic curve. Fails if the recovery failed. The public key is returned in uncompressed format (64 bytes). The function can be used to verify the digital signature of a message by comparing the recovered public key with the sender’s key. .. code-block:: none ecrecover(messageHash: ByteVector, signature: ByteVector): ByteVector :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/154_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` Verify the transaction of the Ethereum blockchain using the following data: * The transaction. * The signature that is generated by the ecsign functions (r, s, and v bytes concatenation). * Sender public key. .. code-block:: none func check(t: ByteVector, signature: ByteVector, publicKey: ByteVector) = { ecrecover(keccak256(t), signature) == publicKey } groth16Verify(ByteVector, ByteVector, ByteVector): Boolean ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Range of functions. Check zk-SNARK by groth16 protocol. .. csv-table:: groth16Verify :file: ../_static/03_ride-language/tables/155_groth16Verify.csv :header-rows: 1 :class: longtable :widths: 5 1 1 :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/156_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 :strong:`Example` .. code-block:: none groth16Verify(vk, proof, inputs) rsaVerify(digestAlgorithmType, ByteVector, ByteVector, ByteVector): Boolean ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Range of functions. Check that the RSA digital signature is valid, i.e. it was created by the owner of the public key. .. csv-table:: rsaVerify :file: ../_static/03_ride-language/tables/157_rsaVerify.csv :header-rows: 1 :class: longtable :widths: 5 1 1 The recommended RSA key module length is at least 2048 bits. Data can be hashed before signing using one of the following algorithms: * MD5 * SHA-1 * SHA-224 * SHA-256 * SHA-384 * SHA-512 * SHA3-224 * SHA3-256 * SHA3-384 * SHA3-512 :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/158_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1 sigVerify(ByteVector, ByteVector, ByteVector): Boolean ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Range of functions. Check that the Curve25519 digital signature is valid, i.e. it was created by the owner of the public key. .. csv-table:: sigVerify :file: ../_static/03_ride-language/tables/159_sigVerify.csv :header-rows: 1 :class: longtable :widths: 5 1 1 :strong:`Parameters` .. csv-table:: Parameters :file: ../_static/03_ride-language/tables/160_Parameters.csv :header-rows: 1 :class: longtable :widths: 1 1