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40 lines
925 B
Go
40 lines
925 B
Go
// errchk $G $D/$F.go
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// Copyright 2009 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package main
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var c1 chan<- chan int
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var c2 chan<- (chan int) // same type as c1 according to gccgo, gofmt
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var c3 chan (<-chan int) // same type as c1 according to 6g
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func main() {
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c1 = c2 // this should be ok, bug 6g doesn't accept it
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c1 = c3 // ERROR "chan"
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}
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/*
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Channel types are parsed differently by 6g then by gccgo and gofmt.
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The channel type specification ( http://golang.org/doc/go_spec.html#Channel_types )
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says that a channel type is either
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chan ElementType
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chan <- ElementType
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<-chan ElementType
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which indicates that the <- binds to the chan token (not to the ElementType).
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So:
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chan <- chan int
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should be parsed as
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chan<- (chan int)
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Both gccgo and gofmt adhere to this, while 6g parses this as
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chan (<-chan int)
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*/
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