Assign to String Pointer

[Luke Mauldin]

If I have a struct as shown below that contains a string pointer, how do I assign or initialize the string pointer?

type foo struct {

strPtr *string

strVal string

}

_ = foo {strVal: "a"} //This works

_ = foo {strPtr: "b"} //This gives me the error: cannot use "b" (type string) as type *string in field value

I am having to use a string pointer type because my struct is being unmarshalled using encoding/json and if the incoming string is null, JSON requires a string pointer to correctly unmarshall the value.  I think that JSON is using reflection to populate the string pointer but I want to be able to set and manipulate the string pointer from regular Go code without using reflection.  Is this possible and if so, how?

Luke

[David Symonds]

Use a helper function or variable:

s := "b"
_ = foo{strPtr: &s}

or

func sPtr(s string) *string { return &s }
_ = foo{strPtr: sPtr("b")}

Dave.

[Evan Shaw]

On Wed, Mar 28, 2012 at 1:03 PM, Luke Mauldin <lukem...@gmail.com> wrote:
> If I have a struct as shown below that contains a string pointer, how do I
> assign or initialize the string pointer?

There's no way to do it in a single expression. You need to do something like:

str := "a"
_ = foo{strPtr: &str}

- Evan

[Luke Mauldin]

Thank you both, your solutions work perfectly.

On Tuesday, March 27, 2012 7:05:49 PM UTC-5, Evan Shaw wrote: