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RE: Re[1]: [CEDET-devel] FW: Parsing of C string constants

From: Berndl, Klaus <klaus.berndl@sd...> - 2003-01-29 17:59

>The L"wide string" notation should probably be handled in the Lexical
>analyzer.

I agree

>This could be an easy piece in semantic 2, but in 1.4,
>you need to modify semantic-c-flex-extensions with something like
>this:

>  "L\\s\""

>which would then need the existing string logic hidden in the lexer
>to finish the task.

Hmm, IMHO this regexp is not enough because this would also match:

"bla bla bla L"
             ^^

IMHO this must be a regexp which matches exactly L and direct behind
a complete string. Is this right? If yes, what is the correct regexp
to match all possible strings, even such ones contained escaped " etc??


>As a rule, you could define a token L, and make a string rule that
>had an optional L in front, but I'm not sure if it would mess up if a
>user tried to define a function or variable L.

Have already tried this, but it seems not to work and IMHO this
is a job for the lexer not for the parser.

Many thanks in advance,
Klaus

Thread View

Thread	Author	Date
RE: Re[1]: [CEDET-devel] FW: Parsing of C string constants	Berndl, Klaus <klaus.berndl@sd...>

Re[3]: [CEDET-devel] FW: Parsing of C string constants

From: Eric M. Ludlam <eric@si...> - 2003-01-29 19:30

>>> "Berndl, Klaus" <klaus.berndl@...> seems to think that:
  [ ... ]
>>This could be an easy piece in semantic 2, but in 1.4,
>>you need to modify semantic-c-flex-extensions with something like
>>this:
>
>>  "L\\s\""
>
>>which would then need the existing string logic hidden in the lexer
>>to finish the task.
>
>Hmm, IMHO this regexp is not enough because this would also match:
>
>"bla bla bla L"
  [ ... ]

it would not match "blah L" because the string "blah L" would be
matched first by the string analyzer, and the L analyzer would not
have the opportunity to see the L inside the string.

The extensions work like this:

  1) Does the regexp "L\\s\"" match
  2) If yes, run some code,

Thus, in your code, you can possibly use the lexical analyzer
recursively on (+1 (point)) to slurp the string.  If that works, then
you are all set, if it fails, return no token, and the L is turned
into a symbol, and the string a string, as opposed to a single wide
string.

Eric

-- 
          Eric Ludlam:                 zappo@..., eric@...
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