Error: '<function-style-cast>': cannot convert from 'const std::string' to 'T'

[a2nath]

struct MyArgs : public argparse::Args
{
    size_t& test = kwarg("-t", "test");
};

What's wrong with this? Why am I forced to use int or unsigned int instead of size_t?

Here's the definition of size_t on Windows

// Definitions of common types
#ifdef _WIN64
    typedef unsigned __int64 size_t;
    typedef __int64          ptrdiff_t;
    typedef __int64          intptr_t;
#else
    typedef unsigned int     size_t;
    typedef int              ptrdiff_t;
    typedef int              intptr_t;
#endif

[a2nath]

Also you can't do this apparently
long& seed = kwarg("s,seed", "seed value for RNG. time(NULL) is the default").set_default(time(NULL));

I have to change time(NULL) to 1 or something simpler. time returns __time64_t and this is the definition in Windows:
typedef __int64 __time64_t;

Edit: even long long& seed doesn't work
long long& seed = kwarg("s,seed", "seed value for RNG. time(NULL) is the default"). This doesn't to be a windows problem

[morrisfranken]

Hi @a2nath,

Thank you for reporting this issue. I've tried to reproduce the problems you're experiencing with size_t, long long, and time(NULL) on Windows, Linux, and macOS, but haven't been able to encounter the same errors in my testing environments.

To help diagnose what's happening in your specific case:

1. Are you experiencing this in an isolated test case (like one of our example files), or when integrating argparse into your larger codebase?
2. Could you provide details about your:
   • Compiler version and flags
   • C++ standard being used
   • Operating system version
   • Any other relevant build configuration

The library should handle these types correctly, so understanding your specific environment will help identify what might be causing the type compatibility issues.

thanks in advance