hash

Use hash to compute the BLAKE2b 256-bit hash of a specified value. The resulting hash value is a Base64Url-encoded string without padding. Strings values are converted directly. Other data type values are converted using their JSON representation. Non-value-level arguments are not allowed.

By convention, the data type <a> is used to represent a type-bound parameter like the value argument in this function.

Basic syntax

To compute the BLAKE2b 256-bit hash of a value, use the following syntax:

(hash value)

Arguments

Use the following argument to specify the value for the hash Pact function:

Argument	Type	Description
value	<a>	Specifies the value to be hashed.

Return value

The hash function returns a string representing the computed hash value.

Examples

The following example demonstrates how to use the hash function to compute a hash for the "hello" string value:

pact> (hash "hello")
"Mk3PAn3UowqTLEQfNlol6GsXPe-kuOWJSCU0cbgbcs8"

Because "hello" is a string value, the hash function computes the BLAKE2b 256-bit hash of the string "hello" and returns the hash value.

(hash { 'foo: 1 })
"h9BZgylRf_M4HxcBXr15IcSXXXSz74ZC2IAViGle_z4"

In this example, { 'foo: 1 } is a JSON object. The hash function computes the BLAKE2b 256-bit hash of the JSON representation of the object and returns the hash value.

The hash function is useful for generating hash values of data for various cryptographic operations in Pact contracts.