message: Simplify to_ast_trait now it is more regular
  Summary: Turn it into an ordering default trait
diff: @@ -45,17 +45,15 @@ pub struct AstModule {
  pub(crate) statement: AstStmt,
  }
  -pub(crate) trait ToAst<T> {
  - fn to_ast(self, span: Span) -> T;
  +pub(crate) trait ToAst: Sized {
  + fn to_ast(self, span: Span) -> Spanned<Self> {
  + Spanned { span, node: self }
  + }
  }
  macro_rules! to_ast_trait {
  ($t1:ty, $t2:ty) => {
  - impl ToAst<$t2> for $t1 {
  - fn to_ast(self, span: Span) -> $t2 {
  - Spanned { span, node: self }
  - }
  - }
  + impl ToAst for $t1 {}
  };
  }
  