49 lines
1.1 KiB
Markdown
49 lines
1.1 KiB
Markdown
# Syntax
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RETRO code consists of a series of whitespace delimited tokens. Each of these can have an optional prefix telling RETRO how to treat the token. If the token lacks a valid prefix, it will be treated as a word name.
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So:
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[prefix][token]
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Prefixes are single character modifiers. They are similar to colors in ColorForth, but are handled via words in the `prefix:` namespace.
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The major prefixes are:
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| Prefix | Used For |
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| ------ | ----------------------------- |
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| @ | Fetch from variable |
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| ! | Store into variable |
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| & | Pointer to named item |
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| # | Numbers |
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| $ | ASCII characters |
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| ' | Strings |
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| ( | Comments |
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| : | Define a word |
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Example:
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````
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(This_is_a_comment)
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(Define_some_words)
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:hello (-)
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'Hello_World! puts nl ;
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:n:square (n-m)
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dup * ;
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(Use_them)
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hello
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#33 n:square
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(More_Things)
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$a (this_is_the_ASCII_'a')
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'Use_underscores_in_place_of_spaces_in_strings
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&puts call
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'Foo var
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#100 !Foo
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@Foo putn
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````
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