How to turn a token stream into a parse tree

Question

I have a built-in lexer that outputs tokens from the input, but I'm not sure how to build the next step in this process - the parsing tree. Does anyone have any good resources or examples of how to do this?

Answer 1

I would recommend http://www.antlr.org/ and, of course, the book of classic dragons.

For a simple language such as JavaScript, it's not difficult to manually steer a recursive descent parser, but it is almost always easier to use a tool like yacc or antlr.

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Answer 2

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%left PLUS, MINUS           # low precedence, evaluated left-to-right
%left TIMES, DIV            # high precedence, left-to-right

expr ::= INT
| expr PLUS expr
| expr MINUS expr
| expr TIMES expr
| expr DIV expr
| LEFT_PAREN expr RIGHT_PAREN

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Answer 3

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Answer 4

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