Format a Go string without printing?

string go formatting string-formatting
Carnegie picture Carnegie · Jun 20, 2012 · Viewed 233.6k times · Source

Is there a simple way to format a string in Go without printing the string?

I can do:

bar := "bar"
fmt.Printf("foo: %s", bar)

But I want the formatted string returned rather than printed so I can manipulate it further.

I could also do something like:

s := "foo: " + bar

But this becomes difficult to read when the format string is complex, and cumbersome when one or many of the parts aren't strings and have to be converted first, like

i := 25
s := "foo: " + strconv.Itoa(i)

Is there a simpler way to do this?

Answer

Sonia picture Sonia · Jun 20, 2012

Sprintf is what you are looking for.

Example

fmt.Sprintf("foo: %s", bar)

You can also see it in use in the Errors example as part of "A Tour of Go."

return fmt.Sprintf("at %v, %s", e.When, e.What)

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