36 lines
909 B
Standard ML
36 lines
909 B
Standard ML
/*
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* This file is part of the Fun programming language.
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* https://fun-lang.xyz/
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*
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* Copyright 2026 Johannes Findeisen
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* Licensed under the terms of the Apache-2.0 license.
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* https://opensource.org/license/apache-2-0
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*
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* Added: 2026-02-19
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*/
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// A simple dynamic match helper.
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// Usage:
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// match(x, [
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// {"when": fun(v) v > 0, "then": fun(v) print("pos")},
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// {"is": 0, "then": fun(v) print("zero")},
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// {"else": fun(v) print("neg or other")}
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// ])
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fun match(value, cases)
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// Iterate cases in order; support keys: is, when, else
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for c in cases
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if (has_key(c, "is"))
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if (value == c["is"])
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th = c["then"]
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return th(value)
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else if (has_key(c, "when"))
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pred = c["when"]
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if (pred(value))
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th = c["then"]
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return th(value)
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else if (has_key(c, "else"))
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el = c["else"]
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return el(value)
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// No match; return nil
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return nil
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