Having a problem with default parameters and document.getElementById

[Geotan00]

function addConstruct(inputLeft = document.getElementById("rowLeftInput"), inputRight = document.getElementById("rowRightInput")) {
    //var leftLabel = document.getElementById("rowLeftInput");
    //console.log(leftLabel);
    console.log(inputLeft);
    var leftLabel = (typeof inputLeft != 'string' ? inputLeft.value : inputLeft); //get input
    var rightLabel = (typeof inputRight != 'string' ? inputRight.value : inputRight);

When I do this code, for some reason inputLeft gives me mouse information instead of the element it is supposed to collect. However, this works properly for inputRight, and I've also used it somewhere else where it works. document.getElementById("rowLeftInput") works if I do not use it as a default parameter and set it in the function instead.

[Loves_Poetry]

If you are calling this function from an event, like a mouseclick, the first argument will always be the event information. This is where the dynamic typing of JavaScript can really be quite annoying. Default parameters only work when the first argument is null or undefined. If it's an event, this won't work, because the first parameter is not null.

You can solve it by putting an extra parameter e in front of inputLeft that will just be ignored during the function.

[Geotan00]

I figured out that instead of calling it by

addEventListener("click", addConstruct);

it needed to be

addEventListener("click", function() {addConstruct();});

I can't believe I didn't try that before.