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Erlang Version: R18.3

when i use this regex in leex(*.xrl):

\/\*(\*(?!\/)|[^*])*\*\/

i got this error:

 bad regexp `illegal character ?'

Hello,

I would like to usw leex in conjunction with yecc on a compiler project of mine.

I am sorry to bother you with this but I encountered a Problem, when trying to parse c-style comments, e.g.,

/* my comment */

as a Single token. The delimiters are not single characters, so a pattern like "[^"]*" as would work for strings doesn't work here.

Instead, lazy (ungreedy) pattern matching would be necessary. Unfortunately, a lazy pattern like

/\*.*?\*/

has not worked.

I am aware, that lazy pattern matching is not a standard feature of a lexer and that I can circumvent this problem by using multiple lexers (see http://flex.sourceforge.net/manual/Why-doesn_0027t-flex-have-non_002dgreedy-operators-like-perl-does_003f.html) but it feels like I am missing something. Especially since the re package for erlang regexes supports lazy patterns (see http://www.erlang.org/doc/man/re.html and https://arifishaq.wordpress.com/2013/11/13/playing-with-regular-expressions/).

If there is any way to lex the input string in a single pass with a single lexer I would appreciate your input.

Best regards
Jörgen

i can not solve that leex..
that's i trying create bbcodes-to-html tool, with leex - first step

https://gist.github.com/221V/ddc9ba71755676a8c344717b095a6c15

can you help me please?
thanks

How to declare for instance a tokenizer where separators are declared in beginning of file to parse ?
I think to EDIFACT or ANSI X12 EDI files where separators are declared in beginning.
It could be nice to pass value of a macro while running lexer, or a syntax to pick characters in some position or catching ereg on file itself, instead having to do templates to generate xrl file and compile at runtime.

The link to the leex and yecc article are stale. I believe this is the new link:

http://relops.com/blog/2014/01/13/leex_and_yecc/

This is currently needed for precise error messages in both https://github.com/graphql-elixir/graphql and https://github.com/absinthe-graphql/absinthe.

https://github.com/rvirding/leex link to 'read more about leex' is a 404 link
to http://relops.com/blog/2014/01/13/leex_and_yecc/

in stackoverflow i found a regex for regex:

/^((?:(?:[^?+*{}()[\]\\|]+|\\.|\[(?:\^?\\.|\^[^\\]|[^\\^])(?:[^\]\\]+|\\.)*\]|\((?:\?[:=!]|\?<[=!]|\?>)?(?1)??\)|\(\?(?:R|[+-]?\d+)\))(?:(?:[?+*]|\{\d+(?:,\d*)?\})[?+]?)?|\|)*)$/

but leex doesnt support ^and$ in match rules, is there anyway else to doing this ?