qstring .arg like thing in pure c++

user4592357

as the title suggests, i need a way to format std::string like QString does with .arg(), but i only wanna use c++.

i know that there's boost class to do that (namely, boost::format) but i don't to attach 3rd party since if i do, the project will become heavy (boost is like 1.2gb)

VRonin

You can look up how QString does it but as you mention, probably boost is the fastest solution. boost::format is header only. No need to link anything. Only the things you use will be added to your program, not the whole 1.2gb

user4592357

well but i still need to choose and include bunch of headers

is it even worth it?

VRonin

😓
It's 1 line in code and 1 line in the project file. Let's no be this lazy, shall we?!

user4592357

how is it 1 line? i added the format.hpp but it has dependencies so i need to add them too

p.s. i can't be lazy cause i'm copying all the needed header files to my project dir :D

p.s.2 or i'm doing something worng?

Konstantin Tokarev

@user4592357 said in qstring .arg like thing in pure c++:

as the title suggests, i need a way to format std::string like QString does with .arg(), but i only wanna use c++.

i know that there's boost class to do that (namely, boost::format) but i don't to attach 3rd party since if i do, the project will become heavy (boost is like 1.2gb)

Boost has a tool to extract only needed parts

user4592357

thanks, but seems like all the folder got copied

here's how i did it:

bcp.exe --boost=..\..\ format C:\Documents\proj\dependencies\boost_1_65_1\boost

VRonin

@user4592357 said in qstring .arg like thing in pure c++:

or i'm doing something worng?

Exactly, you are doing the difficult way. Do not copy every file in your folder.

just add 1 line in the project file (assuming you use qmake on windows): INCLUDEPATH += C:/Boost/boost_1_65_0
re-run qmake
add #include<boost/format.hpp> in your source file

user4592357

@VRonin

the thing is that im not using qt. in that case i'd just use qstring and that's all.

VRonin

@user4592357 The above has nothing to do with Qt, just with the build system you use.

Since you posted here I supposed you were using Qt Creator.
If you use visual studio you should just add C:\Boost\boost_1_65_0 to the "Additional include directories" under Project Properies->C/C++->General

user4592357

@VRonin

i've done that with the whole 1.2gb boost directly. that works

now i need to send the project to my teacher but i don't want to include 1.2gb of files.

and how can including just the header work if it includes other files? i still don't get it

VRonin

What program are you using to write, compile and link your binaries?
What OS are you on?

user4592357

visual studio 2017 on windows 10

VRonin

@VRonin said in qstring .arg like thing in pure c++:

if you use visual studio you should just add C:\Boost\boost_1_65_0 to the "Additional include directories" under Project Properies->C/C++->General

Did you try this before copying the 1.2 GB? of course C:\Boost\boost_1_65_0 is just an example and you should point to the folder where you have downloaded boost

sneubert

What about stringstream?
(http://en.cppreference.com/w/cpp/io/basic_ostringstream)

I always use something like this

#include <iostream>
#include <sstream>
#include <string>

std::ostringstream mystring;
std::string someText = "something";
int number = 11;
mystring << "This is " << someText << " in pure c++ " << number;
std::cout << mystring.str();

Konstantin Tokarev

@sneubert But it works well only for simple formatting, when you need to print columns or specify precision of floating-point numbers, you have to face the nightmare of ios flags

sneubert

@Konstantin-Tokarev
yes u are right even though for my use cases the list of manipulators
(http://en.cppreference.com/w/cpp/io/manip) is sufficient and keep in
mind that only the brave ones are rewarded :-)