Bug 12576 – problem with compile time struct field

the code: template Replace(string base, T...) { template NextAt(string base, string longest_spec, size_t _at0, T...) { } NextAt!(base,"",-1,T) N; } struct _CppFunction { string funcname; } string CppClass1(string name, Clazz)() { enum _CppFunction cf = { }; enum mix = Replace!(" ReturnType Func(Params) { return Mangled(args); }\n", "Func", cf.funcname); return mix; } enum Mixins = CppClass1!("X", typeof(new class { })); the fireworks: $ dmd error1 error1.d(9): Error: template instance NextAt!("\x0a ReturnType Func(Params) {\x0a return Mangled(args);\x0a }\x0a", "", -1, "Func", funcname) cannot use local 'funcname' as parameter to non-global template NextAt(string base, string longest_spec, ulong _at0, T...) error1.d(20): Error: template instance error1._CppFunction.Replace!("\x0a ReturnType Func(Params) {\x0a return Mangled(args);\x0a }\x0a", "Func", funcname) error instantiating error1.d(28): instantiated from here: CppClass1!("X", __anonclass1)

Is this a possible workaround for your 'original' code? I'm not sure it's the actual issue, because the code still fail to compile. template Replace(string base, T...) { template NextAt(string base, string longest_spec, size_t _at0, T...) { } NextAt!(base,"",-1,T) N; } struct _CppFunction { string funcname; } string CppClass1(string name, Clazz)() { enum _CppFunction cf = { }; enum x = cf.funcname; // <--- workaround? enum mix = Replace!(" ReturnType Func(Params) { return Mangled(args); }\n", "Func", /*cf.funcname*/x); // <--- workaround? return mix; } enum Mixins = CppClass1!("X", typeof(new class { }));

yeah, that's what I do now, so this one is probably not the highest priority

While the code in these examples don't compile today, that appears to be because it's incomplete. The underlying issue 5710 has been fixed.