A. Lau A. Lau - 8 months ago 40
Javascript Question

Safari browser-specific error (optional argument)

So I have the following error which only occur in Safari (Apple product, go figure) while not occurring in Chrome or Firefox (code runs perfectly).


SyntaxError: Unexpected token '='. Expected a ')' or a ',' after a parameter declaration.

This is erroring for:
function ajax_general(url, params, title="")

When I remove the optional argument, it runs. Otherwise this occurs. How should I change this to make it also run on Safari?


You are using default function parameters which are not supported by safari currently. Your function:

function ajax_general(url, params, title="")

Default function parameters allow formal parameters to be initialized with default values if no value or undefined is passed.


...is essentially saying, "If no title argument is passed, set title to empty string."

If the third parameter must be set to a value, do it like so:

function ajax_general(url, params, "")

Or depending on your use case, do it inside/outside the function:

var title = "";
function ajax_general(url, params, title);

Chrome and Firefox both have support for default function parameters, but safari unfortunately does not.

For more information: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Default_parameters