javascript - calling function and ignoring callback parameter -


i want call this:

function fwc(a, b, callback) {  dosomestuff(a,b); callback(); }

with this:

fwc (a,b);

sometimes need callback , don't. can cause trouble when call function , ignore callback?

if can't change fwc function, can call :

fwc(a, b, function(){});

this way there won't error when fwc tries call third argument.

if can change it, change 

function fwc(a, b, callback) {     dosomestuff(a,b);     if (callback) callback(); }

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