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compiler/pattern

(match ptrn expr)

Defined at lib/compiler/pattern.lisp:101:2

Determine whether EXPR matches the provided pattern PTRN, returning nil or a lookup of capture names to captured expressions.

(matcher ptrn)

Macro defined at lib/compiler/pattern.lisp:111:2

Create a matcher for the given pattern literal PTRN.

This is intended for views case expressions.

(matches? ptrn expr)

Defined at lib/compiler/pattern.lisp:107:2

Determine whether EXPR matches the provided pattern PTRN.

(pattern ptrn)

Macro defined at lib/compiler/pattern.lisp:38:2

Quote the provided pattern PTRN, suitable for matching with i matches?.

This provides several “magic” symbol prefixes to aid matching:

  • ? marks a metavar, and will be captured. If the second character is &, then this will capture zero or more values.

  • % marks a genvar, which will result in a randomly generated symbol being used in substitutions.

  • $ marks a fullvar, where one can provide the full name to a variable. Use of this is discouraged and should only be used if you really need to detect hidden symbols.

Undocumented symbols

  • (match-always ptrn expr) Defined at lib/compiler/pattern.lisp:118:2