4 ms·

it allows to generate code at basically every scope and to create your own "base language elements" like "struct", "class". AFAIK D does not allow for this, doe

• acehreli 6y ago
  D's templates has always been very strong and useful compared to C++'s. The following example is similar to C macros because it generates code as string and mixes it in as code but you can combine templates as well. This example generates a struct definition. (Edit: formatting) import std; // Entire package for brevity auto memberDef(string type, string name) { return format!" %s %s;"(type, name); } auto memberDefs(string[] members...) { return (members .chunks(2) .map!(pair => memberDef(pair[0], pair[1]))); } auto structDef(string name, string[] members...) { return format!q{ struct %s { %-(%s%) } }(name, memberDefs(members)); } unittest { mixin (structDef("Foo", "int", "i", "double", "d")); auto f = Foo(42, 1.5); assert((f.i == 42) && (f.d == 1.5)); } void main() { }