antlr4 - Precedence in syntax analyst - 


<exp> → <term> assign <exp> | <term>  <term> → <term> exponent <fact> | <term> addop <fact> | <fact>  <fact> → <opeand> relop <operand> | <operand>  <operand> → lb <exp> rb | id

so in case,which 1 has highest,lowest precedence , 1 has equal precedence operator ? ( assign,exponent,addop,relop )

antlr rules not define operator precedence in sense rule matching follows literal sequence of supplied input text.

rather, operator precedence typically defined in user-supplied logic applied in analysis of generated parse-tree. is, given parse-tree node representing parser rule that, example, matches form

x = * b + c

the existence of node signifies necessary sequence of symbols has been matched. logic implemented in parse-tree visitor visits node free define desired relative operator precedence.


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