Perl 4 programmers especially may be surprised to find that as of Perl 5.0 the ampersand & may be omitted in a call to a subroutine if the subroutine has been declared before being used. Actually you can even get around the declare before omit ampersand rule by using the subs.pm pragma, or by pre-declaring (without defining) as in a script like: #!/usr/bin/perl -w use strict; use Tk; sub Mysub; #pre-declare allows calling Mysub() ...Other main/Tk stuff - including call to Mysub() sans &... sub Mysub { ...Mysub stuff... }
Note however that one place the /& reference is sometimes used in perl/Tk in the setting up a callback for a widget. Other references are possible: e.g. /$foo is a reference to the scalar variable $foo (this was true even under perl 4).
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