Variables can shadow types?

[Kevin Ballard]

I noticed some surprising behavior last night. However, I'm not sure if this is actually a bug, or by design. Basically, it seems that variables can shadow types. This is very odd because Go typically has no trouble distinguishing between types and other tokens, so I don't know why a variable name should be allowed to shadow a type name.

Example: (http://play.golang.org/p/KSblIIvoxf)

type aStruct struct {

field int

}

func main() {

aStruct := aStruct{1} // this works

aStruct = aStruct{2} // this doesn't

fmt.Println(aStruct)

}

prog.go:11: aStruct is not a type

Was this intentional, or should I file a bug?

-Kevin

-- 

Kevin Ballard

[Evan Shaw]

Variables and types live in the same namespace, so one can shadow the
other. Types can also shadow variables:
http://play.golang.org/p/qIIAEI6FpR

It's intentional and works this way because otherwise certain
constructs, like conversions, become ambiguous.

- Evan

[Brad Fitzpatrick]

And variables can shadow packages:

http://play.golang.org/p/7Rkq5m2TcO

[Paul Samways]

Is there actually a way of referencing a type in the package scope after it has been shadowed in the function?

[John Asmuth]

I hope you don't take this as snark, because it's not intended that way, but...

Just don't shadow it.

It's all your code, if you're within the package. You can just change your identifiers around.

[si guy]

I ran into this when working with the image package. I learned quickly to call my images something other than "image".