I have what is probably a general Golang question I m a newb

Question

I have what is probably a general Golang question I m a newbie If I have a variable that defined as `interface ` how would I convert the value of that variable to a string

important-appointment-55126 · Answer

If you re sure the variable actually holds a string you can cast it using `foo string ` <https play golang org p Cp3EAcdUeRn>

important-appointment-55126 · Answer

If you want to test whether it s string you can test it during assignment <https play golang org p chpYZVgNBKH>

salmon-account-74572 · Answer

I m sure it does contain a string but `foo string ` type assertion I believe that s called doesn t work Go gives a panic interface conversion error

important-appointment-55126 · Answer

yes type assertion is the correct Go term

salmon-account-74572 · Answer

Being more precise the variable is actually defined as ` interface ` but using ` string ` doesn t work either

important-appointment-55126 · Answer

ah you cannot unfortunately convert slices of interface to slices of another type in one step you have to loop over each item in the slice and build a new slice of the type you want

salmon-account-74572 · Answer

Using a `range` statement to loop over it and convert each element

important-appointment-55126 · Answer

right

salmon-account-74572 · Answer

However if that variable is a field in a struct then you can t use `range` on it yes

important-appointment-55126 · Answer

important-appointment-55126 · Answer

you can use range over any slice wherever it is

salmon-account-74572 · Answer

Hmmm OK Thanks this is very helpful

important-appointment-55126 · Answer

y w

important-appointment-55126 · Answer

You might also like the Gopher s slack space <https invite slack golangbridge org >

important-appointment-55126 · Answer

there s ~50k people on that and a newbies channel as well

salmon-account-74572 · Answer

I ll go join thanks