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This module contains UDA's (User Defined Attributes) either used in the runtime or special UDA's recognized by compiler.
Jacob Carlborg
struct selector;
Use this attribute to attach an Objective-C selector to a method.
This is a special compiler recognized attribute, it has several requirements, which all will be enforced by the compiler:
  • The attribute can only be attached to methods or constructors which have Objective-C linkage. That is, a method or a constructor in a class or interface declared as
  • ,
  • It cannot be attached to a method or constructor that is a template
  • ,
  • The number of colons in the string need to match the number of arguments the method accept.
  • ,
  • It can only be used once in a method declaration
extern (Objective-C)
class NSObject
 this() @selector("init");
 static NSObject alloc() @selector("alloc");
 NSObject initWithUTF8String(in char* str) @selector("initWithUTF8String:");
 ObjcObject copyScriptingValue(ObjcObject value, NSString key, NSDictionary properties)
struct gnuAbiTag;
Use this attribute to declare an ABI tag on a C++ symbol.
ABI tag is an attribute introduced by the GNU C++ compiler. It modifies the mangled name of the symbol to incorporate the tag name, in order to distinguish from an earlier version with a different ABI.
This is a special compiler recognized attribute, it has a few requirements, which all will be enforced by the compiler:
  • There can only be one such attribute per symbol.
  • ,
  • The attribute can only be attached to an extern(C++) symbol (struct, class, enum, function, and their templated counterparts).
  • ,
  • The attribute cannot be applied to C++ namespaces. This is to prevent confusion with the C++ semantic, which allows it to be applied to namespaces.
  • ,
  • The string arguments must only contain valid characters for C++ name mangling which currently include alphanumerics and the underscore character.
  • ,
This UDA is not transitive, and inner scope do not inherit outer scopes' ABI tag. See examples below for how to translate a C++ declaration to D. Also note that entries in this UDA will be automatically sorted alphabetically, hence gnuAbiTag("c", "b", "a") will appear as @gnuAbiTag("a", "b", "c").
// ---- foo.cpp
struct [[gnu::abi_tag ("tag1", "tag2")]] Tagged1_2
    struct [[gnu::abi_tag ("tag3")]] Tagged3
        [[gnu::abi_tag ("tag4")]]
        int Tagged4 () { return 42; }
Tagged1_2 inst1;
// ---- foo.d
@gnuAbiTag("tag1", "tag2") struct Tagged1_2
    // Notice the repetition
    @gnuAbiTag("tag1", "tag2", "tag3") struct Tagged3
        @gnuAbiTag("tag1", "tag2", "tag3", "tag4") int Tagged4 ();
extern __gshared Tagged1_2 inst1;