There's a logical operator for that: xor 

if ( !$x == !$y) ) # bool($x) == bool($y)
if ( !$x != !$y  ) # bool($x) != bool($y)

[download]
can be written as 
if ( !($x xor $y) ) # bool($x) == bool($y)
if (   $x xor $y  ) # bool($x) != bool($y)

[download]

Unforunately, both sets have readability issues.

In reply to Re^5: Burned by precedence rules (== true) by ikegami
in thread Burned by precedence rules by vrk

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