}
}
+ fn lower_global_asm(&mut self, ga: &GlobalAsm) -> P<hir::GlobalAsm> {
+ P(hir::GlobalAsm {
+ asm: ga.asm,
+ ctxt: ga.ctxt,
+ })
+ }
+
fn lower_variant(&mut self, v: &Variant) -> hir::Variant {
Spanned {
node: hir::Variant_ {
}
ItemKind::Mod(ref m) => hir::ItemMod(self.lower_mod(m)),
ItemKind::ForeignMod(ref nm) => hir::ItemForeignMod(self.lower_foreign_mod(nm)),
+ ItemKind::GlobalAsm(ref ga) => hir::ItemGlobalAsm(self.lower_global_asm(ga)),
ItemKind::Ty(ref t, ref generics) => {
hir::ItemTy(self.lower_ty(t), self.lower_generics(generics))
}
//
// match <sub_expr> {
// <pat> => <body>,
- // [_ if <else_opt_if_cond> => <else_opt_if_body>,]
// _ => [<else_opt> | ()]
// }
arms.push(self.arm(hir_vec![pat], body_expr));
}
- // `[_ if <else_opt_if_cond> => <else_opt_if_body>,]`
- // `_ => [<else_opt> | ()]`
+ // _ => [<else_opt>|()]
{
- let mut current: Option<&Expr> = else_opt.as_ref().map(|p| &**p);
- let mut else_exprs: Vec<Option<&Expr>> = vec![current];
-
- // First, we traverse the AST and recursively collect all
- // `else` branches into else_exprs, e.g.:
- //
- // if let Some(_) = x {
- // ...
- // } else if ... { // Expr1
- // ...
- // } else if ... { // Expr2
- // ...
- // } else { // Expr3
- // ...
- // }
- //
- // ... results in else_exprs = [Some(&Expr1),
- // Some(&Expr2),
- // Some(&Expr3)]
- //
- // Because there also the case there is no `else`, these
- // entries can also be `None`, as in:
- //
- // if let Some(_) = x {
- // ...
- // } else if ... { // Expr1
- // ...
- // } else if ... { // Expr2
- // ...
- // }
- //
- // ... results in else_exprs = [Some(&Expr1),
- // Some(&Expr2),
- // None]
- //
- // The last entry in this list is always translated into
- // the final "unguard" wildcard arm of the `match`. In the
- // case of a `None`, it becomes `_ => ()`.
- loop {
- if let Some(e) = current {
- // There is an else branch at this level
- if let ExprKind::If(_, _, ref else_opt) = e.node {
- // The else branch is again an if-expr
- current = else_opt.as_ref().map(|p| &**p);
- else_exprs.push(current);
- } else {
- // The last item in the list is not an if-expr,
- // stop here
- break
- }
- } else {
- // We have no more else branch
- break
- }
- }
-
- // Now translate the list of nested else-branches into the
- // arms of the match statement.
- for else_expr in else_exprs {
- if let Some(else_expr) = else_expr {
- let (guard, body) = if let ExprKind::If(ref cond,
- ref then,
- _) = else_expr.node {
- let then = self.lower_block(then, false);
- (Some(cond),
- self.expr_block(then, ThinVec::new()))
- } else {
- (None,
- self.lower_expr(else_expr))
- };
-
- arms.push(hir::Arm {
- attrs: hir_vec![],
- pats: hir_vec![self.pat_wild(e.span)],
- guard: guard.map(|e| P(self.lower_expr(e))),
- body: P(body),
- });
- } else {
- // There was no else-branch, push a noop
- let pat_under = self.pat_wild(e.span);
- let unit = self.expr_tuple(e.span, hir_vec![]);
- arms.push(self.arm(hir_vec![pat_under], unit));
- }
- }
+ let wildcard_arm: Option<&Expr> = else_opt.as_ref().map(|p| &**p);
+ let wildcard_pattern = self.pat_wild(e.span);
+ let body = if let Some(else_expr) = wildcard_arm {
+ P(self.lower_expr(else_expr))
+ } else {
+ self.expr_tuple(e.span, hir_vec![])
+ };
+ arms.push(self.arm(hir_vec![wildcard_pattern], body));
}
let contains_else_clause = else_opt.is_some();
projects / rust.git / commitdiff