Modern C++ configure files?

[paulross80]

Hello. I would like to create a more modern C++ configure file
My config.hpp.in file:

namespace x
{
    constexpr static bool debug_mode =
    #ifdef X_DEBUG
        true;
    #else
        false;
    #endif
}

But the generated config.hpp file ends up like this:

namespace x
{
    constexpr static bool debug_mode =
    #ifdef X_DEBUG
        true;
    #else
        false;
    #endif
}

My project code:

target("x")
    set_kind("static")
    -- Add source files
    add_files("cpp/lib/**.cpp")
    --set_configvar("X_DEBUG", is_mode("debug")) -- this doesn't work for some reason
    if is_mode("debug") then
        set_configvar("X_DEBUG", true)
    end
    -- Config file
    set_configdir("$(buildir)/config")
    add_configfiles("config/config.hpp.in")

[paulross80]

I have tried to do this:

if is_mode("debug") then
    set_configvar("X_DEBUG", "true", { quote = false })
else
    set_configvar("X_DEBUG", "false", { quote = false })
end

but the result is this:

namespace x
{
    constexpr static bool debug_mode = #define X_DEBUG false;
}

[waruqi]

you need to add ${define X_DEBUG}

${define X_DEBUG}

namespace x
{
    constexpr static bool debug_mode =
    #ifdef X_DEBUG
        true;
    #else
        false;
    #endif
}

https://xmake.io/#/manual/project_target?id=targetset_configvar

[paulross80]

It didn't work. The generated file looks like this (for release mode):

/* #undef X_DEBUG */

namespace x
{
    constexpr static bool debug_mode =
    #ifdef X_DEBUG
        true;
    #else
        false;
    #endif
}

I just want to get the true or false literal value. Is this possible?

[waruqi]

debug_mode = ${X_DEBUG}

[paulross80]

Everything is perfect. Thank you!

namespace x
{
    constexpr static bool debug_mode = true;
    constexpr static int version_major = 0;
    constexpr static int version_minor = 0;
    constexpr static int version_alter = 1;
    constexpr static unsigned long version_build = 202403021330;
}