antlr

ANTLR: Is there a simple example?

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Note: this answer is for ANTLR3! If you’re looking for an ANTLR4 example, then this Q&A demonstrates how to create a simple expression parser, and evaluator using ANTLR4. You first create a grammar. Below is a small grammar that you can use to evaluate expressions that are built using the 4 basic math operators: +, … Read more

lexers vs parsers

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What parsers and lexers have in common: They read symbols of some alphabet from their input. Hint: The alphabet doesn’t necessarily have to be of letters. But it has to be of symbols which are atomic for the language understood by parser/lexer. Symbols for the lexer: ASCII characters. Symbols for the parser: the particular tokens, … Read more