31 lines
636 B
Markdown
31 lines
636 B
Markdown
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# PL/0 implementation
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Idea: implement a PL/0 compiler and VM from scratch.
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https://en.wikipedia.org/wiki/PL/0
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Grammer is defined in EBNF.
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* [foo] is optional, so foo must be present 0 or 1 times.
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* {foo} is repeated 0 or more times.
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## Language
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The final top level block is equivalent to main().
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## Recursive descent parser
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A mechanical conversion from the BNF form to code.
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- accept() checks if the next token is the starting one.
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- expect() requires the next token is a certain one.
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## Other implementations
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https://github.com/crcx/PL0-Language-Tools
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## Components
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Tokeniser
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Parser
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Generator
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