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https://github.com/unknwon/the-way-to-go_ZH_CN.git
synced 2025-08-12 06:36:43 +08:00
44 lines
1.1 KiB
Go
Executable File
44 lines
1.1 KiB
Go
Executable File
// panic_defer_convint.go
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package main
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import (
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"fmt"
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"math"
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)
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func main() {
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l := int64(15000)
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if i, err := IntFromInt64(l); err!= nil {
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fmt.Printf("The conversion of %d to an int32 resulted in an error: %s", l, err.Error())
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} else {
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fmt.Printf("%d converted to an int32 is %d", l, i)
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}
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fmt.Println()
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l = int64(math.MaxInt32 + 15000)
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if i, err := IntFromInt64(l); err!= nil {
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fmt.Printf("The conversion of %d to an int32 resulted in an error: %s", l, err.Error())
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} else {
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fmt.Printf("%d converted to an int32 is %d", l, i)
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}
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}
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func ConvertInt64ToInt(l int64) int {
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if math.MinInt32 <= l && l <= math.MaxInt32 {
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return int(l)
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}
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panic(fmt.Sprintf("%d is out of the int32 range", l))
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}
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func IntFromInt64(l int64) (i int, err error) {
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defer func() {
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if e := recover(); e != nil {
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err = fmt.Errorf("%v", e)
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}
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}()
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i = ConvertInt64ToInt(l)
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return i, nil
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}
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/* Output:
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15000 converted to an int32 is 15000
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The conversion of 2147498647 to an int32 resulted in an error: 2147498647 is out of the int32 range
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*/ |