var fn_toggleBoolean=function(q_a){ return Boolean(Math.abs(Number(q_a)-1)); }; /** * fn_toggleBoolean(true)===false * fn_toggleBoolean(false)===true * * Thus: * fn_toggleBoolean(fn_toggleBoolean(true))===true */ /** * Another way */ var fn_toggleBoolean_b=function(q_a){ return q_a==true ? false : true; }; /** * Okay okay. The second way looks much simpler * but the first one is the most elegant one, * isn't it? :D */