37 lines
741 B
Forth
37 lines
741 B
Forth
# example program: constructing functions out of order
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#
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# We construct a factorial function with separate base and recursive cases.
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# Compare factorial.mu.
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#
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# This isn't a very tasteful example, just a basic demonstration of
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# possibilities.
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def factorial n:num -> result:num [
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local-scope
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load-inputs
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<factorial-cases>
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]
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after <factorial-cases> [
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# if n=0 return 1
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return-unless n, 1
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]
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after <factorial-cases> [
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# return n * factorial(n - 1)
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{
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break-unless n
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x:num <- subtract n, 1
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subresult:num <- factorial x
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result <- multiply subresult, n
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return result
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}
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]
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def main [
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1:num <- factorial 5
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# trailing space in next line is to help with syntax highlighting
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$print [result: ], 1:num, [
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]
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]
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