Given how much better the AST is from having the receiver be separate, it makes me wonder if HIR would benefit just as much…

[cjgillot]

HIR bundles the self expression and the arguments of method calls in a single vector in the hir::ExprKind::MethodCall variant.

Unbundling this in AST in #100232 showed a significant simplification of client code.

Suggested by @nagisa in #100232 (comment)

[cjgillot]

Steps:

• add an extra &'hir Expr<'hir> field to the hir::ExprKind::MethodCall variant;
• adapt lowering in rustc_ast_lowering::expr to lower the AST receiver into this field, and not with the arguments;
• adapt all the using code to use this extra field where they were using the 0th argument (beware the off-by-one lurking in the shadow).

[shourya5]

@rustbot claim

[TaKO8Ki]

#101261