Get nth return value from function in Go

Question

I have started learning Go yesterday and so far I am fascinated. But I bumped to a problem.

Lets assume that function returns multiple vars (awesome feature). How should I use only nth value and not first n-1 values? In example I just want to check whether key exists in hash map but do nothing with value.

var value, hasElement = myMap[key]

The error I get is

main.go:15: value declared and not used

If I just print value it will all be fine but that is not good.

Possible duplicate of [Go: multiple value in single-value context](http://stackoverflow.com/questions/28227095/go-multiple-value-in-single-value-context) and [Return map like 'ok' in Golang on normal functions](http://stackoverflow.com/questions/28487036/return-map-like-ok-in-golang-on-normal-functions) — icza, Sep 04 '16 at 15:57

fmt · Accepted Answer · 2016-09-04T15:10:15.360

5

In Go, the character _ is a placeholder indicating that you don't care about the value. Therefore, you can do

var _, hasElement = myMap[key]

which will ignore the first return value.

This extends to functions with any number of return values:

var a, _, _, d, e, _ = bigFunction()

edited Sep 04 '16 at 15:10

answered Sep 04 '16 at 15:03

fmt

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Thanks mate! This language keeps fascinating me. – Rouz Sep 04 '16 at 15:05
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The first snippet is invalid Go code. Replace `map` with some other variable name. – Charlie Tumahai Sep 04 '16 at 15:06

Get nth return value from function in Go

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