Added USING_STD_NAMESPACE macro to text module

[ahmedyarub]

resolves #1324

Added USING_STD_NAMESPACE macro since "-DUSING_STD_NAMESPACE is now needed for all of the tesseract library, not just for training."

[sovrasov]

There are no mentions of this macro in the Opencv code? Why do you need this?

[LaurentBerger]

I think problem is explained here
Problem is : at line using tesseract 4.00.0alpha

I don't understand problem at line there is a std:: before vector but no std before string.

Using std::string does not comply with Google's coding conventions.

@stweil

I don't think macro is good idea but problem must be solved.

@fifothekid if you need tesseract now insert std before string and problem is solved

[ahmedyarub]

@LaurentBerger exactly

[stweil]

@LaurentBerger, using that macro is the new correct way to solve the problem with string. I'm afraid that Google's coding conventions are something which we cannot change. The usage of std:: is inconsistent, yes.

In addition to the macro, I'd also add a comment which explains why the macro is needed. Maybe some day it won't be needed any more.

[sovrasov]

@fifothekid argee, comment is needed here and eliminate merge commit please.

[LaurentBerger]

Macro is here and only used by tesseract( on my knowledge). May be insert in precomp.hpp :

#include <string>
using std::string;

would be readable

@stweil I have got some difficulties to find rule in google coding convetion. Is it this?

[gachiemchiep]

@LaurentBerger Thanks man, your code worked like a charm.

[ahmedyarub]

@LaurentBerger they simply don't accept adding std:: before string and what you said makes sense
so how can this be resolved?

[alalek]

👍

[amitdo]

Tesseract is now at beta 1 stage.

This version uses std:string everywhere. USE_STD_NAMESPACE is not needed anymore.