mirror of
https://github.com/ceph/go-ceph
synced 2024-12-22 06:10:09 +00:00
e01eb03284
Our first operation is generating sizes for various caller-allocated buffers. The WithSizes function "suggests" sizes to an anonymous function that takes a size as an argument and returns a hint how sucessful the attempt was. If required the same function is called again with a larger size. Errors and other results of that anonymous function are "communicated" with variables of the surrounding scope in wich the function is defined. Signed-off-by: John Mulligan <jmulligan@redhat.com> Signed-off-by: Sven Anderson <sven@redhat.com>
57 lines
1.0 KiB
Go
57 lines
1.0 KiB
Go
package retry
|
|
|
|
import (
|
|
"fmt"
|
|
)
|
|
|
|
var errTooSmall = fmt.Errorf("too small")
|
|
|
|
func fakeComplexOp(v []string) error {
|
|
if len(v) < 30 {
|
|
fmt.Println("too small:", len(v))
|
|
return errTooSmall
|
|
}
|
|
fmt.Println("good size:", len(v))
|
|
return nil
|
|
}
|
|
|
|
func ExampleWithSizes() {
|
|
var err error
|
|
WithSizes(1, 128, func(size int) Hint {
|
|
buf := make([]string, size)
|
|
// do something complex with buf
|
|
err = fakeComplexOp(buf)
|
|
return DoubleSize.If(err == errTooSmall)
|
|
})
|
|
// Output:
|
|
// too small: 1
|
|
// too small: 2
|
|
// too small: 4
|
|
// too small: 8
|
|
// too small: 16
|
|
// good size: 32
|
|
}
|
|
|
|
func fakeComplexOp2(v []string, s *int) error {
|
|
if len(v) < 30 {
|
|
fmt.Println("too small:", len(v))
|
|
*s = 30
|
|
return errTooSmall
|
|
}
|
|
fmt.Println("good size:", len(v))
|
|
return nil
|
|
}
|
|
|
|
func ExampleWithSizes_hint() {
|
|
var err error
|
|
WithSizes(1, 128, func(size int) Hint {
|
|
buf := make([]string, size)
|
|
// do something complex with buf
|
|
err = fakeComplexOp2(buf, &size)
|
|
return Size(size).If(err == errTooSmall)
|
|
})
|
|
// Output:
|
|
// too small: 1
|
|
// good size: 30
|
|
}
|