Golang在模板中用逗号分隔项目

Question

I am trying to display a list of comma separated values, and don't want to display a comma after the last item (or the only item if there is only one).

My code so far:

Equipment:
    {{$equipment := .Equipment}}
    {{ range $index, $element := .Equipment}}
        {{$element.Name}}
        {{if lt $index ((len $equipment) -1)}}
            ,
        {{end}}
    {{end}}

The current output: Equipment: Mat , Dumbbell , How do I get rid of the trailing comma

Answer 1

A nice trick you can use is:

Equipment:
    {{$equipment := .Equipment}}
    {{ range $index, $element := .Equipment}}
        {{if $index}},{{end}}
        {{$element.Name}}
    {{end}}

This works because the first index is 0, which returns false in the if statement. So this code returns false for the first index, and then places a comma in front of each following iteration. This results in a comma separated list without a leading or trailing comma.