text/template issue: Is there a way to identity the last element of ranging array?

[Googol Lee]

For example:

func main() {

    t := template.Must(template.New("abc").Parse("{{ range . }}{{ . }}, {{ end }}."))                                                                        

    a := []string{"Alice", "Bob", "Cherry", "Dark"}

    t.Execute(os.Stdout, a)

}

The output is:

Alice, Bob, Cherry, Dark, .

But I want to get:

Alice, Bob, Cherry, Dark.

Notice after the last element "Dark" expect dot, not comma.

I know I can write a function to do this, but is there a easy way to do it in template?

[Martin Schnabel]

from http://go.pkgdoc.org/text/template:

If a "range" action initializes a variable, the variable is set to the
successive elements of the iteration. Also, a "range" may declare two
variables, separated by a comma:

$index, $element := pipeline

then you can use the index to check for the first element. like this:
http://play.golang.org/p/-pR3Bn6efy

[Googol Lee]

I know how to check first element. But how to check the last one?

[roger peppe]

On 18 June 2012 12:31, Googol Lee <goog...@gmail.com> wrote:
> I know how to check first element. But how to check the last one?

It seems to me that Martin's answer solved your problem admirably.

But if you really want to check for the last element, there are
a few ways of doing it, by defining your own functions.

Here are a couple of examples:

http://play.golang.org/p/NWhyfft8Ba
http://play.golang.org/p/Y-CZ2TBSGU

[Carlos Castillo]

If you are defining functions in templates you could just use strings.Join

http://play.golang.org/p/3tnjtT8-Qw

[Googol Lee]

Thank you. The last function seems pretty good.

On Monday, June 18, 2012 7:46:36 PM UTC+8, rog wrote:

[Googol Lee]

The last function is wired. Template parser pass a string to last, and the Len of value "a" is the string length, not array.

On Monday, June 18, 2012 7:46:36 PM UTC+8, rog wrote:

[roger peppe]

Yes, the call I made only worked by coincidence...
The intention was to pass the slice into the last
function, not the element. This is better:
http://play.golang.org/p/VM4rSuEG2A