mirror of
https://github.com/golang/go
synced 2024-11-21 16:04:45 -07:00
d482c163be
This shortens, simplifies and regularizes the code significantly.
(Improvements to reflect could make another step.)
Passes all.bash.
One semantic change occurs: The String() method changes
behavior. It used to run only for string formats such as %s and %q.
Instead, it now runs whenever the item has the method and the
result is then processed by the format as a string. Besides the
regularization, this has three effects:
1) width is honored for String() items
2) %x works for String() items
3) implementations of String that merely recur will recur forever
Regarding point 3, example from the updated documentation:
type X int
func (x X) String() string { return Sprintf("%d", x) }
should cast the value before recurring:
func (x X) String() string { return Sprintf("%d", int(x)) }
R=rsc
CC=golang-dev
https://golang.org/cl/1613045
30 lines
531 B
Go
30 lines
531 B
Go
// $G $D/$F.go && $L $F.$A && ./$A.out
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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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import "fmt"
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type T int
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func (t T) String() string { return fmt.Sprintf("T%d", int(t)) }
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const (
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A T = 1 << (1 << iota)
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B
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C
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D
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E
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)
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func main() {
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s := fmt.Sprintf("%v %v %v %v %v", A, B, C, D, E)
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if s != "T2 T4 T16 T256 T65536" {
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println("type info didn't propagate in const: got", s)
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panic("fail")
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}
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}
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