32 lines
1 KiB
Markdown
32 lines
1 KiB
Markdown
# Forth
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Implement an evaluator for a very simple subset of Forth.
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[Forth](https://en.wikipedia.org/wiki/Forth_%28programming_language%29)
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is a stack-based programming language. Implement a very basic evaluator
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for a small subset of Forth.
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Your evaluator has to support the following words:
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- `+`, `-`, `*`, `/` (integer arithmetic)
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- `DUP`, `DROP`, `SWAP`, `OVER` (stack manipulation)
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Your evaluator also has to support defining new words using the
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customary syntax: `: word-name definition ;`.
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To keep things simple the only data type you need to support is signed
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integers of at least 16 bits size.
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You should use the following rules for the syntax: a number is a
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sequence of one or more (ASCII) digits, a word is a sequence of one or
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more letters, digits, symbols or punctuation that is not a number.
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(Forth probably uses slightly different rules, but this is close
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enough.)
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Words are case-insensitive.
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## Submitting Incomplete Solutions
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It's possible to submit an incomplete solution so you can see how others have completed the exercise.
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