unless (...) is the equivalent of if (not (...))

yes this is obviously true, but can be error prone in the case of complex conditions.

De_Morgan's_laws are useful in this case to do the correct translation between the plain and the negated form of a (possibly comlpex) condition.

I was suggested to investigate such laws when i had an Untillian Headache

L*

There are no rules, there are no thumbs..
Reinvent the wheel, then learn The Wheel; may be one day you reinvent one of THE WHEELS.

In reply to Re^2: Simplify code in Perl with "unless" loop -- De Morgan's laws by Discipulus
in thread Simplify code in Perl with "unless" condition by Chaoui05

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