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[Caml-list] assert + -pp = wrong line number and filename in assert message
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Paul Stodghill
- Paul Stodghill
- Xavier Leroy
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| Date: | -- (:) |
| From: | Xavier Leroy <Xavier.Leroy@i...> |
| Subject: | Re: [Caml-list] assert + -pp = wrong line number and filename in assert message |
> The "assert" construct generates an exception which contains the file > name and line number where the "assert" appears. Character number, actually. > However, when a preprocessor is used (with the -pp option), the file name > and line number that are recorded are relative to the preprocessor > output file and not to original source file, even when the > '# linenum "filename"' directives are inserted in the preprocessor > output. Right. OCaml has a peculiar way of treating positions in source code: on parsing, it remembers minimal information (absolute character numbers in the input, regardless of # lineno "filename" directives), and it's only when an error is detected that it re-scans the input to convert the character numbers into file name + line number. This works well for error reporting, but causes problems with "assert", the compiler-generated "Match_failure" exceptions, and certain uses of Camlp4. All this will have to be addressed at some point, although it's rather painful to do right. Best regards, - Xavier Leroy ------------------- Bug reports: http://caml.inria.fr/bin/caml-bugs FAQ: http://caml.inria.fr/FAQ/ To unsubscribe, mail caml-list-request@inria.fr Archives: http://caml.inria.fr