[ $x => $y ] is the same as [ $x, $y ] which is the essentially the same as 

my $ary = ( $x, $y );
my $aryRef =  \ @ary;

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And $x <= $y is just a boolean expression that will give a false (0) result if $x > $y and true value (1) otherwise.

$aryRef->[ 0/1 ] will return either $ary[ 0 ] or $ary[ 1 ].

Putting it all together, you get an expression that will construct an anonymous array containing $x, $y, then dereferences that anonmous array and uses the boolean result of the comparison to select the greater of the two values before assigning it to the scalar.

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In reply to Re^3: getting the highest value in a simpler way by BrowserUk
in thread getting the highest value in a simpler way by replicant4

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