On Friday, October 7, 2016 at 4:57:29 PM UTC-7, Ian Lance Taylor wrote: > > On Fri, Oct 7, 2016 at 4:18 PM, sbkim via golang-nuts > <golan...@googlegroups.com <javascript:>> wrote: > > > > If an operand of fmt.Printf implements method String() string, > fmt.Printf > > respects it and uses it. > > But it doesn't if an operand is a a struct that has such an element. > > > > For example, https://play.golang.org/p/QJC7Q9Kpch: > > package main > > > > import "fmt" > > > > type Int int > > > > func (i Int) String() string { return fmt.Sprintf("Int(%d)", int(i)) } > > > > type Box struct{ elem Int } > > > > func main() { > > format := "%[1]v\t%+[1]v\t%#[1]v\n" > > i := Int(73) > > fmt.Printf(format, i) > > fmt.Printf(format, &Box{i}) > > fmt.Printf(format, []Int{i}) > > fmt.Printf(format, map[string]Int{"hello":i}) > > } > > > > Output: > > Int(73) Int(73) 73 > > &{73} &{elem:73} &main.Box{elem:73} > > [Int(73)] [Int(73)] []main.Int{73} > > map[hello:Int(73)] map[hello:Int(73)] map[string]main.Int{"hello":73} > > > > In the second line of the output, none of the format specifiers ("%v", > > "%+v", "%#v") calls the String() method of Int, in contrast to the first > > line. > > > > Isn't this an inconsistency that should be fixed? Or is it intended > > behavior? > > It does seem like a bug. Please open a bug report at > https://golang.org/issue . Thanks. >
Thanks. I filed a bug at https://github.com/golang/go/issues/17409. -- You received this message because you are subscribed to the Google Groups "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
