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		00f9f0c056
		
	
	
	
	
		
			
			note that sortmain.go has been run through hg gofmt; only the formatting of the day initializers changed. i'm happy to revert that formatting if you'd prefer. stop on error in doc/progs/run R=r CC=golang-dev https://golang.org/cl/850041
		
			
				
	
	
		
			83 lines
		
	
	
	
		
			1.6 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			83 lines
		
	
	
	
		
			1.6 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
| // $G $D/$F.go && $L $F.$A && ./$A.out
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| 
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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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| 
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| package main
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| 
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| import "fmt"
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| 
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| const (
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| 	a = 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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| 
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| var x = []int{1, 2, 3}
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| 
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| func f(x int, len *byte) {
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| 	*len = byte(x)
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| }
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| 
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| func whatis(x interface{}) string {
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| 	switch xx := x.(type) {
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| 	default:
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| 		return fmt.Sprint("default ", xx)
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| 	case int, int8, int16, int32:
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| 		return fmt.Sprint("signed ", xx)
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| 	case int64:
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| 		return fmt.Sprint("signed64 ", int64(xx))
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| 	case uint, uint8, uint16, uint32:
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| 		return fmt.Sprint("unsigned ", xx)
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| 	case uint64:
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| 		return fmt.Sprint("unsigned64 ", uint64(xx))
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| 	case nil:
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| 		return fmt.Sprint("nil ", xx)
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| 	}
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| 	panic("not reached")
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| }
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| 
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| func whatis1(x interface{}) string {
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| 	xx := x
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| 	switch xx.(type) {
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| 	default:
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| 		return fmt.Sprint("default ", xx)
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| 	case int, int8, int16, int32:
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| 		return fmt.Sprint("signed ", xx)
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| 	case int64:
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| 		return fmt.Sprint("signed64 ", xx.(int64))
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| 	case uint, uint8, uint16, uint32:
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| 		return fmt.Sprint("unsigned ", xx)
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| 	case uint64:
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| 		return fmt.Sprint("unsigned64 ", xx.(uint64))
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| 	case nil:
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| 		return fmt.Sprint("nil ", xx)
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| 	}
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| 	panic("not reached")
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| }
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| 
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| func check(x interface{}, s string) {
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| 	w := whatis(x)
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| 	if w != s {
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| 		fmt.Println("whatis", x, "=>", w, "!=", s)
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| 		panic("fail")
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| 	}
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| 
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| 	w = whatis1(x)
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| 	if w != s {
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| 		fmt.Println("whatis1", x, "=>", w, "!=", s)
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| 		panic("fail")
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| 	}
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| }
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| 
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| func main() {
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| 	check(1, "signed 1")
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| 	check(uint(1), "unsigned 1")
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| 	check(int64(1), "signed64 1")
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| 	check(uint64(1), "unsigned64 1")
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| 	check(1.5, "default 1.5")
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| 	check(nil, "nil <nil>")
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| }
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