jquery - Javascript documentation notation -

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• what brackets around arguments mean when reading documentation method? [duplicate] 3 answers

i've seen lot , of time can figure out means, there have been times when bit confused. looking @ documentation on jquery see this:

.toggleclass( function [, state ] )

what bracket notation comma , state mean exactly?

any info awesome.

thanks!

everything between brackets [] optional.

in case means state can omitted, , function still work.