A warning for subs that you declare but then don't use would be really annoying for those who are doing more advanced things behind-the-scenes. I might want to declare a subroutine name, but then define it at run-time.
Indeed in the very same script I had 
sub killp;

*killp = DEBUG ? \&_killp_debug : \&_killp_real;

[download]
although I bet that many Perl hackers wouldn't regard this as a good practice.

However we already do e.g. 

no strict 'refs';
# and
no warnings 'uninitialized';

[download]
all the time. A 'used only once' warning as suggested by someone else wouldn't be that bad after all.
I don't run into this problem because I like parens that give perl a bit of extra help with the parsing (and keep maintenance programmers from getting too confused too).
Well, that's to a very large extent a matter of personal preferences, just like so many other things in Perl. I find code having as few parentheses as possible to be best readable.

In reply to Re^2: Warning for "unused sub declarations"? by blazar
in thread Warning for "unused sub declarations"? by blazar

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