Description
What version of Go are you using (go version)?
go version go1.11.2 linux/amd64
Does this issue reproduce with the latest release?
Yes
What operating system and processor architecture are you using (go env)?
go env Output
GOARCH="amd64" GOBIN="" GOCACHE="/home/vss/.cache/go-build" GOEXE="" GOFLAGS="" GOHOSTARCH="amd64" GOHOSTOS="linux" GOOS="linux" GOPATH="/home/vss/gorepo" GOPROXY="" GORACE="" GOROOT="/usr/local/go" GOTMPDIR="" GOTOOLDIR="/usr/local/go/pkg/tool/linux_amd64" GCCGO="gccgo" CC="gcc" CXX="g++" CGO_ENABLED="1" GOMOD="" CGO_CFLAGS="-g -O2" CGO_CXXFLAGS="-g -O2" CGO_FFLAGS="-g -O2" CGO_LDFLAGS="-L/usr/lib" PKG_CONFIG="pkg-config" GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0 -fdebug-prefix-map=/tmp/go-build489605010=/tmp/go-build -gno-record-gcc-switches"
What did you do?
package main
import (
"fmt"
)
type Ref struct {
i int64
}
type ARef Ref
func findRef(refs []Ref, ref Ref) bool {
for _, r := range refs {
if r == ref {
return true
}
}
return false
}
func main() {
ta := []ARef{{0}, {1}}
found := findRef([]Ref(ta), Ref{0})
fmt.Println(found)
}
https://play.golang.org/p/pDZu77EZwEp
What did you expect to see?
The program should be compiled without error
What did you see instead?
prog.go:24:24: cannot convert ta (type []ARef) to type []Ref
Similar issues have been discussed but closed due to age or a valid reason. I have a Ref type which represents a technology ref. To differentiate a ref for each type, I created new type like ARef because I don;t want them to used one for the other. However I need to write several functions like findRef which operate on Ref type. Here one of the suggested way is to create a slice of Ref and copy elements, this is inefficient and not elegant. IMHO, a language should be consistent in different aspects. Allowing conversion of two types having the same underlying type but not allowing conversion of slices of the same types does not seem consistent.
Though I talked about slices of types in this description which I am practically facing right now, the problem can easily generalized by extended it to other complex type like pointers, array of pointers, maps etc.