Re: Error reporting with YACC (or Bison)

Hi Eric,


You could try to insert into your grammar "error-productions", most
frequently used errors for some obvious cases. For example :


        pascal_for : FOR term ASSIGN integer_expression TO integer_expression DO
statement
                                          | FOR term ASSIGN integer_expression TO
integer_expression { yyerror("DO expected"); ... }
                                                statement
                                          | ...
                                          ;


But be care, inserting extra-actions in some places of your grammar could
produce more ambiguity of your grammar. But anyway (with more headache) you
could try some workarounds...


Best Regards,
Timur Safin
mailto:timur@lantel.ru http://timur.lanit.ru
mailto:timur@intersystems.ru


> I used Flex and Bison to write an interpreter for a simple c-like
> language. When Bison encounters a syntax error it spits out "parse
> error". I want to give more descriptive error messages, such
> as "expecting semicolon after line 3". How would I go about this?

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