template parameter list syntax

[Paul Backus]

On Saturday, 19 January 2019 at 16:36:34 UTC, Carl Sturtivant 
wrote:
>
> Why is it that when template arguments are supplied at the 
> point of use, the nice distinguishing syntax of x!(a,b,c) is 
> obligatory, yet when template parameters are supplied at the 
> point of definition the syntax is not distinguished in the same 
> way with a bang !

At the point of use, ! is needed to ensure there's no ambiguity 
between instantiating a template and calling a function.

At the point of definition, there's no ambiguity, so the ! is not 
needed.