match-replace ( object pattern1 pattern2 -- result ) - Factor Documentation

match-replace ( object pattern1 pattern2 -- result )
Pattern matching

Vocabulary
match

Inputs

object an object

pattern1 an object

pattern2 an object

Outputs

result an object

Word description
Matches the object against pattern1. The pattern match variables in pattern1 are assigned the values from the matching object. These are then replaced into the pattern2 pattern match variables.

Examples

USING: match prettyprint ; IN: scratchpad MATCH-VARS: ?a ?b ; { 1 2 } { ?a ?b } { ?b ?a } match-replace .
{ 2 1 }

See also
match-cond , MATCH-VARS:

Definition

USING: kernel namespaces ;

IN: match

: match-replace ( object pattern1 pattern2 -- result )
[ match [ "Pattern does not match" throw ] unless* ] dip
swap [ replace-patterns ] with-variables ;