From:	Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: bison
Date:	5 Dec 2000 13:04:23 GMT
Organization:	Aachen University of Technology (RWTH)
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References:	<90anr9$ji0$1 AT lacerta DOT tiscalinet DOT it>
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[This is in no way particular to DJGPP...]

abacuc <f DOT onorati AT tiscalinet DOT it> wrote:
> I read some info for bison and i realize a parser but it's a entire
> program...

No, it isn't. Or only if you request a complete program from Bison.
You normall get a sourcecode from Bison that compiles into a single
user-visible function yyparse().

> i want to know if is it possible to realize a function parser
> (e.g. a function that receive a string like input parameter like 2+3-4*12
> and return a double output) that i can use in a my project.

That's really easy. The trick is to define your own 'yylex' (or
yyinput(), if you're using Flex along with Bison) that reads out of a
string instead of a file.



-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.

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