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A generalised version of case. This case* accepts an equality predicate (the built-in case uses eqv?) and evaluates its cases instead of implicitly quoting them.
Generalised-case works like R5RS case, except that it accepts an extra argument after the key and the data in the clauses are evaluated. The special form has the name case*.
The extra argument is the equality predicate which is used to determine equality of members. The key is passed as the first parameter, the datum to match is passed as the second parameter.
(use generalised-case) (define (foo-maker) "FOO") (case* "foo" string-ci=? (("bar" (foo-maker) "qux") (display "bar, foo or qux\n") 1) (else (display "We got something else\n") 2)) ;; returns 1 and prints the following: ;; bar, foo or qux
- 1.3 Fix in define-macro version by Reed Sheridan
- 1.2 Fix in macro by Peter Bex
- 1.1 Apply some optimisations [Thanks to Christian Jaeger]
- 1.0 Initial release
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