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46 lines
1.1 KiB
Text
46 lines
1.1 KiB
Text
# Local Variables
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RETRO does not provide local variables. Similar functionality
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can be achieved using globals along with the `v:preserve`
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combinator, but this can lead to ugly code.
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Consider:
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'Counter var
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:average (...n-v)
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&Counter [ #0 !Counter
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[ + &Counter v:inc ] times @Counter / ] v:preserve ;
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:run-tests
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#0 !Counter
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#1 #2 #3 #4 #3 average n:put nl &Counter v:inc
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#10 #20 #30 #40 #3 average n:put nl &Counter v:inc
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#11 #21 #31 #41 #3 average n:put nl &Counter v:inc
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@Counter n:put sp '_tests_finished s:put nl ;
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run-tests
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The code implemented here allows for wrapping the most recent
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word within a `v:preserve` clause, letting the above definition
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of `test` become:
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:average (...n-v)
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#0 !Counter [ + &Counter v:inc ] times @Counter / ;
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&Counter make-local
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And if you need multiple variables to be localized:
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:average ... ;
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{ &Array &Of &Variables } locals
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# The Code
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~~~
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:make-local (a-)
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here [ compile:lit
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d:last.xt compile:lit
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&v:preserve compile:call
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compile:ret ] dip d:last d:xt store ;
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:locals (a-) &make-local a:for-each ;
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~~~
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