Getting type information from name as a string

[in...@marczahn.de]

Hi,

for a code generator I want to get a type of a string which is passed by an argument by go generate. So I have sth. like "[]int" and now I need to know if it is a slice/rangeable, of type int etc. Is this somehow possible?

I cannot have a predefined map from strings to types because it is supposed to be generic.

[Marcin Romaszewicz]

That's what the reflect package does,

https://play.golang.org/p/M7gNcKjOmMM

-- Marcin

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[roger peppe]

So you have a string which contains a Go type expression, and you want to find out attributes of that type? In general you can't do that without knowing the context that the expression is to be evaluated in. For example, the string "T" could be any kind of type if T is defined as a type somewhere.

Assuming you know the package that the type expression is in, you could use https://godoc.org/golang.org/x/tools/go/packages to load it up, then use https://golang.org/pkg/go/ast to parse the type expression and use the results of the first to look up symbols from the resulting AST.

  cheers,

    rog.

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[in...@marczahn.de]

@rog: I guess this could be the answer. I saw it at mockgen later as well. Thank you for that hint.