Enums

Enums are sets of distinct, named values of the same type. In C, this may be an actual enum declaration, or even a set of defines. Importantly, the values of an enum should be known at compile time.

To define an enum type, add @:build(ammer.def.Enum.build(..., ..., ...)) to a Haxe enum abstract. The first argument parameter for ammer.def.Enum.build should be a string identifying the native C type name. The second argument should be an FFI type. The third argument should be the ammer library this type belongs to.

Enums should only contain variable declarations, one for each enum variant.

Example: enum definition

@:build(ammer.def.Enum.build("int", Int32, Foobar))
enum abstract FoobarEnum(Int) from Int to Int {
  @:ammer.native("FOOBAR_VAL1") var Val1;
  @:ammer.native("FOOBAR_VAL2") var Val2;
  // ...
}

In this example, FoobarEnum is an enum in the Foobar library. The C type underlying this enum is a regular int. There are two variants: Val1 and Val2, which have the integer values available in the constants FOOBAR_VAL1 and FOOBAR_VAL2 at compile time.

Compilation

In order for Haxe to be able to use ammer enums like regular enum abstracts, the value of each variant must be known at compile time. ammer will automatically extract the appropriate values by invoking the C compiler.

Linking

Enums should be linked with the parent library using the @:ammer.sub(...) metadata to avoid compilation errors. See linking subdefinitions.