Once you use the Go(/Jinja/Perl) syntax once or twice, then putting a minus sign to remove whitespace will be easily understood.
I am interested in an alternative that you find more elegant.
Why not make it a filter/pipeline (I haven't used template/text in ages, does it support this?), like in Django {{ thing|trimleft }}.
So "{{ foo -}} bar" renders the same as "{{ foo }}bar".
Once you use the Go(/Jinja/Perl) syntax once or twice, then putting a minus sign to remove whitespace will be easily understood.
I am interested in an alternative that you find more elegant.