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cif-statementantlrgrammarantlrworks

the if satement does not work with my grammar

I have an issue with my if statement with my grammar, wich can be found here http://sd-g1.archive-host.com/membres/up/24fe084677d7655eb57ba66e1864081450017dd9/CNew.txt . When I type for example in Ctrl+D :

  int k = 0;
  if ( k ==0 ){
       return k;
  }

the tree parser stops at "if(" , and the console does not state any reason. Does anyone know where the issue may comes from please ?

Solution

  • Assuming the entry point of your grammar is translation_unit, it looks like the parser simply stops after it matched a single external_declaration. Try adding the EOF (end of file) token at the end of that rule so that the parser is forced to match the entire input:

    translation_unit
    : external_declaration+ EOF
    ;

    However, I don't see how an external_declaration would ever match an if-statement (a selection_statement) in your grammar. Perhaps you want to add a statement to your external_declaration:

    translation_unit
scope Symbols; // entire file is a scope
@init {
  $Symbols::types = new HashSet();
}
    : (external_declaration)+ EOF
    ;

external_declaration
    : function_definition
    | declaration
    | statement
    ;

    after which your input will get properly parsed.