56 lines
1.1 KiB
Forth
56 lines
1.1 KiB
Forth
# An Experiment in Vocabularies
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Retro provides a single dictionary. By convention, we use short
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prefixes for namespaces and have some limited ability to hide
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definitions using `{{`, `---reveal---`, and `}}`. But it's
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sometimes nice to be able to hide words and reveal them only
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when actually needed.
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These words provide a minimal form of vocabulary by allowing
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temporarily relinking the main dictionary to follow a different
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path. The idea is to provide a word that points to a data stru-
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cture with the current Dictonary pointer. When in use, the main
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Dictionary is relinked to this, and when closed, the stored
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pointer is updated.
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~~~
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{{
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'a var 'b var
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---reveal---
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:forth (-) @b @a @Dictionary swap store !Dictionary ;
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:with (a-) @Dictionary swap dup fetch !Dictionary !a !b ;
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:voc (s-) d:create @Dictionary comma ;
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}}
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~~~
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# Some Tests
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```
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:a #3 n:put nl ;
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:b #5 n:put nl ;
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a b
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'test voc &test with
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:a #1 n:put nl ;
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:b #2 n:put nl ;
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a b
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forth
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a b
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&test
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:b #7 n:put nl ;
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a b
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&test with
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a b
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forth
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'foo voc &foo with
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:b #9 n:put nl ;
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a b
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forth
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a b
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&test with a b :c #100 n:put nl ; c forth
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c
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&foo with c forth
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&test with c forth
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```
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