Doing it that way both if and unless will fail. If you don't declare the sub up front you need to call the sub with parens: check_disk_space(). There is some weirdness though. With if the error is 
Bareword "check_disk_space" not allowed while "strict subs" in use...

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and with unless 
Bareword "check_disk_space" not allowed while "strict subs" in use...
Bareword "check_disk_space" not allowed while "strict subs" in use...

[download]
Not sure why it comes up twice.

I prefer to have all my subs at the end of the script and always call them with the parens. I use parens with perl built ins too if the args have any level of complexity. YMMV.

In reply to Re^3: unless weirdness by wfsp
in thread unless weirdness by Plankton

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