impl_scope

kas_core

Macro impl_scope 

Source 
impl_scope!() { /* proc-macro */ }
Expand description

Scope supporting impl Self and advanced attribute macros

This macro facilitates definition of a type (struct, enum or union) plus implementations via impl Self { .. } syntax: Self is expanded to the type’s name, including generics and bounds (as defined on the type).

Caveat: rustfmt can not yet format contents (see rustfmt#5254, rustfmt#5538).

Note: prefer impl_self over this macro unless using impl_default. This macro will be removed once RFC 3681 (default field values) is stable in this crate’s MSRV.

See impl_tools::impl_scope for full documentation.

§Special attribute macros

Additionally, impl_scope! supports special attribute macros evaluated within its scope:

  • #[impl_default]: implement [Default] using field initializers (which are not legal syntax outside of impl_scope!)
  • #[widget]: implement kas::Widget trait family

Note: matching these macros within impl_scope! does not use path resolution. Using #[kas_macros::impl_default] would resolve the variant of this macro which doesn’t support field initializers.