From 6d8829e931fa92d9228f6b67e0832195cd477248 Mon Sep 17 00:00:00 2001 From: Robert Griesemer Date: Mon, 25 Jan 2010 12:03:53 -0800 Subject: [PATCH] A <- token in an expression may introduce a channel type. Fixes #530. R=rsc CC=golang-dev https://golang.org/cl/193091 --- src/pkg/go/parser/parser.go | 17 +++++++++++++++-- src/pkg/go/parser/parser_test.go | 2 ++ 2 files changed, 17 insertions(+), 2 deletions(-) diff --git a/src/pkg/go/parser/parser.go b/src/pkg/go/parser/parser.go index f5e8f839eb..a680d862e5 100644 --- a/src/pkg/go/parser/parser.go +++ b/src/pkg/go/parser/parser.go @@ -1221,14 +1221,27 @@ func (p *parser) parseUnaryExpr() ast.Expr { } switch p.tok { - case token.ADD, token.SUB, token.NOT, token.XOR, token.ARROW, token.AND, token.RANGE: + case token.ADD, token.SUB, token.NOT, token.XOR, token.AND, token.RANGE: pos, op := p.pos, p.tok p.next() x := p.parseUnaryExpr() return &ast.UnaryExpr{pos, op, p.checkExpr(x)} + case token.ARROW: + // channel type or receive expression + pos := p.pos + p.next() + if p.tok == token.CHAN { + p.next() + value := p.parseType() + return &ast.ChanType{pos, ast.RECV, value} + } + + x := p.parseUnaryExpr() + return &ast.UnaryExpr{pos, token.ARROW, p.checkExpr(x)} + case token.MUL: - // unary "*" expression or pointer type + // pointer type or unary "*" expression pos := p.pos p.next() x := p.parseUnaryExpr() diff --git a/src/pkg/go/parser/parser_test.go b/src/pkg/go/parser/parser_test.go index 2f7bace6ff..9e37551623 100644 --- a/src/pkg/go/parser/parser_test.go +++ b/src/pkg/go/parser/parser_test.go @@ -32,6 +32,8 @@ var validPrograms = []interface{}{ `package main;`, `package main; import "fmt"; func main() { fmt.Println("Hello, World!") }` + "\n", `package main; func main() { if f(T{}) {} }` + "\n", + `package main; func main() { _ = (<-chan int)(x) }` + "\n", + `package main; func main() { _ = (<-chan <-chan int)(x) }` + "\n", } -- 2.50.0