exist var? OR exist object ?

how determine existence?

by Ruben Ruiz Perez

JavaScript

function existVar(variable1) { //How can I check the existence of variable in javascript?
    if (typeof variable1 !== 'undefined') return true;
    else return false;
}

function existObj(selector1) {
    //How can I check the existence of an element in jQuery?
    if ($(selector1).length > 0) return true
    else return false;

}

if (existObj(document)) alert('Result yes');
else alert('Result no');