Built-in Functions

Constant denoting the ASCII charset

Constant:   CHARSET_ASCII:integer = 0

Constant denoting the Latin-1 charset ISO-8859-1

Constant:   CHARSET_LATIN1:integer = 1

idx integer list [<l>] → <a>

idx string object object:<{o}> → <a>

Index LIST at IDX, or get value with key IDX from OBJECT.

string string → string

Decode STRING from unpadded base64

string string → string

Encode STRING as unpadded base64

src object:<{row}> binding binding:<{row}> → <a>

Special form evaluates SRC to an object which is bound to with BINDINGS over subsequent body statements.

→ object:{public-chain-data}

Get transaction public metadata. Returns an object with 'chain-id', 'block-height', 'block-time', 'prev-block-hash', 'sender', 'gas-limit', 'gas-price', and 'gas-fee' fields.

x x:<a> -> <b> y x:<b> -> <c> value <a> → <c>

Compose X and Y, such that X operates on VALUE, and Y on the results of X.

str-list [string] → string

Takes STR-LIST and concats each of the strings in the list, returning the resulting string

value <a> ignore1 <b> → <a>

value <a> ignore1 <b> ignore2 <c> → <a>

value <a> ignore1 <b> ignore2 <c> ignore3 <d> → <a>

Lazily ignore arguments IGNORE* and return VALUE.

value <a> list [<a>] → bool

key <a> object object:<{o}> → bool

value string string string → bool

Test that LIST or STRING contains VALUE, or that OBJECT has KEY entry.

value * → *

Continue a previously started nested defpact.

namespace string user-guard guard admin-guard guard → string

Create a namespace called NAMESPACE where ownership and use of the namespace is controlled by GUARD. If NAMESPACE is already defined, then the guard previously defined in NAMESPACE will be enforced, and GUARD will be rotated in its place.

Top level only: this function will fail if used in module code.

ns string → object:{described-namespace}

Describe the namespace NS, returning a row object containing the user and admin guards of the namespace, as well as its name.

Top level only: this function will fail if used in module code.

values [<a>] → [<a>]

Returns from a homogeneous list of VALUES a list with duplicates removed. The original order of the values is preserved.

count integer list <a[[<l>],string]> → <a[[<l>],string]>

keys [string] object object:<{o}> → object:<{o}>

Drop COUNT values from LIST (or string), or entries having keys in KEYS from OBJECT. If COUNT is negative, drop from end. If COUNT exceeds the interval (-2^63,2^63), it is truncated to that range.

test bool msg string → bool

Fail transaction with MSG if pure expression TEST is false. Otherwise, returns true.

msg string tests [bool] → bool

Run TESTS in order (in pure context, plus keyset enforces). If all fail, fail transaction. Short-circuits on first success.

min-version string → bool

min-version string max-version string → bool

Enforce runtime pact version as greater than or equal MIN-VERSION, and less than or equal MAX-VERSION. Version values are matched numerically from the left, such that '2', '2.2', and '2.2.3' would all allow '2.2.3'.

Top level only: this function will fail if used in module code.

from integer to integer inc integer → [integer]

from integer to integer → [integer]

Returns a sequence of numbers from FROM to TO (both inclusive) as a list. INC is the increment between numbers in the sequence. If INC is not given, it is assumed to be 1. Additionally, if INC is not given and FROM is greater than TO assume a value for INC of -1. If FROM equals TO, return the singleton list containing FROM, irrespective of INC's value. If INC is equal to zero, this function will return the singleton list containing FROM. If INC is such that FROM + INC > TO (when FROM < TO) or FROM + INC < TO (when FROM > TO) return the singleton list containing FROM. Lastly, if INC is such that FROM + INC < TO (when FROM < TO) or FROM + INC > TO (when FROM > TO), then this function fails.

app x:<a> -> bool list [<a>] → [<a>]

Filter LIST by applying APP to each element. For each true result, the original value is kept.

app x:<a> y:<b> -> <a> init <a> list [<b>] → <a>

Iteratively reduce LIST by applying APP to last result and element, starting with INIT.

template string vars [*] → string

Interpolate VARS into TEMPLATE using {}.

value <a> → string

Compute BLAKE2b 256-bit hash of VALUE represented in unpadded base64-url. Strings are converted directly while other values are converted using their JSON representation. Non-value-level arguments are not allowed.

value <a> → <a>

Return provided value.

cond bool then <a> else <a> → <a>

Test COND. If true, evaluate THEN. Otherwise, evaluate ELSE.

base integer val integer → string

Represent integer VAL as a string in BASE. BASE can be 2-16, or 64 for unpadded base64URL. Only positive values are allowed for base64URL conversion.

charset integer input string → bool

Check that a string INPUT conforms to the a supported character set CHARSET. Character sets currently supported are: 'CHARSET_LATIN1' (ISO-8859-1), and 'CHARSET_ASCII' (ASCII). Support for sets up through ISO 8859-5 supplement will be added in the future.

x <a[[<l>],string,object:<{o}>]> → integer

Compute length of X, which can be a list, a string, or an object.

elems * → [*]

Create list from ELEMS. Deprecated in Pact 2.1.1 with literal list support.

→ [string]

List modules available for loading.

Top level only: this function will fail if used in module code.

length integer value <a> → [<a>]

Create list by repeating VALUE LENGTH times.

app x:<b> -> <a> list [<b>] → [<a>]

Apply APP to each element in LIST, returning a new list of results.

namespace string → string

Set the current namespace to NAMESPACE. All expressions that occur in a current transaction will be contained in NAMESPACE, and once committed, may be accessed via their fully qualified name, which will include the namespace. Subsequent namespace calls in the same tx will set a new namespace for all declarations until either the next namespace declaration, or the end of the tx.

Top level only: this function will fail if used in module code.

→ string

Return ID if called during current pact execution, failing if not.

→ string

Obtain current pact build version.

Top level only: this function will fail if used in module code.

Schema type for data returned from 'chain-data'.

Fields:   chain-id:string   block-height:integer   block-time:time   prev-block-hash:string   sender:string   gas-limit:integer   gas-price:decimal

key string → decimal

Parse KEY string or number value from top level of message data body as decimal.

key string → integer

Parse KEY string or number value from top level of message data body as integer.

→ <a>

key string → <a>

Read KEY from top level of message data body, or data body itself if not provided. Coerces value to their corresponding pact type: String -> string, Number -> integer, Boolean -> bool, List -> list, Object -> object.

key string → string

Parse KEY string or number value from top level of message data body as string.

key string object object:<{o}> → object:<{o}>

Remove entry for KEY from OBJECT.

binding binding:<{r}> → <a>

Special form binds to a yielded object value from the prior step execution in a pact. If yield step was executed on a foreign chain, enforce endorsement via SPV.

list [<a>] → [<a>]

Reverse LIST.

values [<a>] → [<a>]

fields [string] values [object:<{o}>] → [object:<{o}>]

Sort a homogeneous list of primitive VALUES, or objects using supplied FIELDS list.

str-val string → integer

base integer str-val string → integer

Compute the integer value of STR-VAL in base 10, or in BASE if specified. STR-VAL can be up to 512 chars in length. BASE must be between 2 and 16, or 64 to perform unpadded base64url conversion. Each digit must be in the correct range for the base.

str string → [string]

Takes STR and returns a list of single character strings

count integer list <a[[<l>],string]> → <a[[<l>],string]>

keys [string] object object:<{o}> → object:<{o}>

Take COUNT values from LIST (or string), or entries having keys in KEYS from OBJECT. If COUNT is negative, take from end. If COUNT exceeds the interval (-2^63,2^63), it is truncated to that range.

default <a> action <a> → <a>

Attempt a pure ACTION, returning DEFAULT in the case of failure. Pure expressions are expressions which do not do i/o or work with non-deterministic state in contrast to impure expressions such as reading and writing to a table.

→ string

Obtain hash of current transaction as a string.

x <a> → string

Returns type of X as string.

field string app x:<a> -> bool value object:<{row}> → bool

Utility for use in 'filter' and 'select' applying APP to FIELD in VALUE.

object object:<{y}> → object:<{y}>

object object:<{y}> target-chain string → object:<{y}>

Yield OBJECT for use with 'resume' in following pact step. With optional argument TARGET-CHAIN, target subsequent step to execute on targeted chain using automated SPV endorsement-based dispatch.

f x:<a> y:<b> -> <c> list1 [<a>] list2 [<b>] → [<c>]

Combine two lists with some function f, into a new list, the length of which is the length of the shortest list.