30 lines
860 B
Forth
30 lines
860 B
Forth
# example program: maintain multiple counters with isolated lexical scopes
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# (spaces)
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def new-counter n:num -> default-space:space [
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default-space <- new location:type, 30
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load-inputs # initialize n
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]
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def increment-counter outer:space/names:new-counter, x:num -> n:num/space:1 [
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local-scope
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load-inputs
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0:space/names:new-counter <- copy outer # setup outer space; it *must* come from 'new-counter'
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n/space:1 <- add n/space:1, x
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]
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def main [
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local-scope
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# counter A
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a:space/names:new-counter <- new-counter 34
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# counter B
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b:space/names:new-counter <- new-counter 23
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# increment both by 2 but in different ways
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increment-counter a, 1
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b-value:num <- increment-counter b, 2
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a-value:num <- increment-counter a, 1
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# check results
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$print [Contents of counters], 10/newline
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$print [a: ], a-value, [ b: ], b-value, 10/newline
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]
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