Documentation for infix ≢ assembled from the following pages:

Language documentation: Operators §

From Operators

(Operators) infix ≢ §

multi sub infix:<≢>($a,$b --> Bool:D)

Set inequality operator.

Returns True if $a and $b are not identical. Equivalent to !(==).

say (1, 2, 3) ≢ (1, 2, 4); # OUTPUT: «True␤» 
say (1, 2, 3) ≢ (1, 3, 2); # OUTPUT: «False␤» 

Language documentation: Sets, bags, and mixes §

From Sets, bags, and mixes

(Sets, bags, and mixes) infix ≢ §

Returns True if $a and $b are not identical, else False. More information, Wikipedia definition.