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| author | Jakub Wieczorek <jakub@jakub.cc> | 2014-09-29 22:45:26 +0200 |
|---|---|---|
| committer | Jakub Wieczorek <jakub@jakub.cc> | 2014-09-30 18:54:03 +0200 |
| commit | 5254ccc7c16f232ddd8788b8a3e7c89ffa82532a (patch) | |
| tree | db7e6a84d48507636001d3dd7093d53f5fa4fef4 /src/libsyntax | |
| parent | e53f4a6b94623076a912df0c770c591d710c5de0 (diff) | |
| download | rust-5254ccc7c16f232ddd8788b8a3e7c89ffa82532a.tar.gz rust-5254ccc7c16f232ddd8788b8a3e7c89ffa82532a.zip | |
Update after the fall out from the syntax::ptr changes
Diffstat (limited to 'src/libsyntax')
| -rw-r--r-- | src/libsyntax/ext/expand.rs | 66 |
1 files changed, 36 insertions, 30 deletions
diff --git a/src/libsyntax/ext/expand.rs b/src/libsyntax/ext/expand.rs index 76ca33cc2b8..fa3ccc8cf32 100644 --- a/src/libsyntax/ext/expand.rs +++ b/src/libsyntax/ext/expand.rs @@ -70,8 +70,6 @@ pub fn expand_expr(e: P<ast::Expr>, fld: &mut MacroExpander) -> P<ast::Expr> { // Desugar ExprIfLet // From: `if let <pat> = <expr> <body> [<elseopt>]` ast::ExprIfLet(pat, expr, body, mut elseopt) => { - let span = e.span; - // to: // // match <expr> { @@ -90,23 +88,33 @@ pub fn expand_expr(e: P<ast::Expr>, fld: &mut MacroExpander) -> P<ast::Expr> { let else_if_arms = { let mut arms = vec![]; loop { - // NOTE: replace with 'if let' after snapshot - match elseopt { - Some(els) => match els.node { - // else if - ast::ExprIf(cond, then, elseopt_) => { - let pat_under = fld.cx.pat_wild(span); - elseopt = elseopt_; - arms.push(ast::Arm { - attrs: vec![], - pats: vec![pat_under], - guard: Some(cond), - body: fld.cx.expr_block(then) - }); - } - _ => break - }, - None => break + let elseopt_continue = elseopt + .and_then(|els| els.and_then(|els| match els.node { + // else if + ast::ExprIf(cond, then, elseopt) => { + let pat_under = fld.cx.pat_wild(span); + arms.push(ast::Arm { + attrs: vec![], + pats: vec![pat_under], + guard: Some(cond), + body: fld.cx.expr_block(then) + }); + elseopt.map(|elseopt| (elseopt, true)) + } + _ => Some((P(els), false)) + })); + match elseopt_continue { + Some((e, true)) => { + elseopt = Some(e); + } + Some((e, false)) => { + elseopt = Some(e); + break; + } + None => { + elseopt = None; + break; + } } } arms @@ -115,10 +123,7 @@ pub fn expand_expr(e: P<ast::Expr>, fld: &mut MacroExpander) -> P<ast::Expr> { // `_ => [<elseopt> | ()]` let else_arm = { let pat_under = fld.cx.pat_wild(span); - let else_expr = match elseopt { - Some(els) => els, - None => fld.cx.expr_lit(span, ast::LitNil) - }; + let else_expr = elseopt.unwrap_or_else(|| fld.cx.expr_lit(span, ast::LitNil)); fld.cx.arm(span, vec![pat_under], else_expr) }; @@ -133,23 +138,24 @@ pub fn expand_expr(e: P<ast::Expr>, fld: &mut MacroExpander) -> P<ast::Expr> { // Desugar support for ExprIfLet in the ExprIf else position ast::ExprIf(cond, blk, elseopt) => { - let elseopt = elseopt.map(|els| match els.node { + let elseopt = elseopt.map(|els| els.and_then(|els| match els.node { ast::ExprIfLet(..) => { // wrap the if-let expr in a block + let span = els.span; let blk = P(ast::Block { view_items: vec![], stmts: vec![], - expr: Some(els), + expr: Some(P(els)), id: ast::DUMMY_NODE_ID, rules: ast::DefaultBlock, - span: els.span + span: span }); fld.cx.expr_block(blk) } - _ => els - }); - let if_expr = fld.cx.expr(e.span, ast::ExprIf(cond, blk, elseopt)); - noop_fold_expr(if_expr, fld) + _ => P(els) + })); + let if_expr = fld.cx.expr(span, ast::ExprIf(cond, blk, elseopt)); + if_expr.map(|e| noop_fold_expr(e, fld)) } ast::ExprLoop(loop_block, opt_ident) => { |