34 lines
994 B
Markdown
34 lines
994 B
Markdown
# The many faces of EForth
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EForth is delightfully minimalist approach to Forth originated by Bill Muench and Dr. C. H. Ting.
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In its original form metacompilation is avoided.
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## Directories
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* reference/ - EForth Reference Material
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* circleforth/ - A minimalist Forth modeled after toy Lisps.
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* ueforth/ - micro EForth - EForth refactored to allow source boostraping.
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## EForth Quirks
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EForth uses `FOR..NEXT` in favor of `DO..LOOP`:
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[FOR/NEXT](https://github.com/TG9541/stm8ef/wiki/eForth-FOR-..-NEXT).
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This construct has the odd property that it iterates one "extra" time for zero.
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```
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: FOO 10 FOR R@ . NEXT ; FOO
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10 9 8 7 6 5 4 3 2 1 0 ok
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```
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To permit a more ordinary loop the `AFT` word is used in the sequence `FOR..AFT..THEN..NEXT`.
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```
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: FOO 10 FOR ( 1st time only ) AFT R@ . THEN NEXT ; FOO
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9 8 7 6 5 4 3 2 1 0 ok
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```
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The even more enigmatic `FOR..WHILE..NEXT..ELSE..THEN` is used in place of `DO..LEAVE..LOOP`.
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It allows a while condition to early out of a counted loop.
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