My habit in any language, going back many years, has been to debug using the equivalent of print() and so I did at first in Perl. I appreciate the convenience of say(); it allows me to concentrate on properly quoting what I wish to say, without hanging , qq{\n} to the end of the statement.

Print-debug statements must be disabled in production. One may comment them out individually but some can be missed. For a time, I felt more secure writing, e.g.:

    say q{$myvar: }, $myvar if $::Debug;
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But that's too much work and leads to other difficulties.

When I learned of it, I enthusastically adopted Smart::Comments, which permits:

    ### $myvar
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... with the same effect as the say() code above; except that disabling is simpler and can also be more flexible. Complex structures are dumped (internally using Data::Dumper) in exactly the same way. (Please see In Defense of Smart::Comments.) The big fat shorcoming is that all smart output goes to STDERR.

So, I forked S::C into Devel::Comments, which permits output to be sent to one's choice of output streams or files. Other features are planned. Needless to say, in future, this will be my first choice.