Re: [Boost-users] Reading key-value pairs from a string

Subject: Re: [Boost-users] Reading key-value pairs from a string
From: Eric Niebler (eric_at_[hidden])
Date: 2009-04-13 13:35:13

Zdravko Monov wrote:
> Dear boost-users,
> 
> I am currently working on a C++ project that includes reading and 
> parsing some files.
> Given a string with certain file contents S, I would like to attempt to 
> compare it against a certain pattern. In particular, the contents have 
> the form key : value. Certain keys are obligatory, while others may or 
> may not exist (my program then supplies the default values).
> Can you recommend me a boost facility that can help me reading this type 
> of data? My problem is that between key, : and value there could be 
> blank spaces, tabs etc. The type of value could be a string, an int, or 
> double.

It sounds like Boost.Xpressive would be a good fit for you. It's a regex 
engine that lets you nest actions with the regex. Here is an example 
that does pretty much exactly what you're looking for: parses a string 
containing key/value pairs into a std::map.

http://www.boost.org/doc/libs/1_38_0/doc/html/xpressive/user_s_guide.html#boost_xpressive.user_s_guide.semantic_actions_and_user_defined_assertions

HTH,

-- 
Eric Niebler
BoostPro Computing
http://www.boostpro.com