This template should be placed on the documentationsubpage (not the template page itself) of any template that should not be substituted (and transcluded instead).
((substituted or transcluded)) – if-then-else metatemplate that checks if a template is currently being substituted or transcluded
((always substitute)) – For the doc of the above templates; prints a message asking for it be substituted.
((never substitute)) – The reverse of ((always substitute)). For the doc of templates which should not be substituted; prints a message asking for it not to be substituted.
((may be substituted)) – For the doc of templates whose substitution is optional.
((substitution)) – Allows free-fill description of whether the template should be substituted and under what conditions.