JavaScript: Browser JS Console Object Syntax Error

By Xah Lee. Date: .

Uncaught SyntaxError: Unexpected token {

browser console js object syntax error 20161027
Common error when using brower console to evaluate a JavaScript object literal expression. Google Chrome Browser, 2016-10-27.

One common error when using console is that when you type this:

{"x":3, "y":4};

and you get an error:

Uncaught SyntaxError: Unexpected token

It's a quirk in the JavaScript language. It thinks you are using a code block, not object.

solution is to wrap the object by parenthesis, like this:

({"x":3, "y":4})

In Google Chrome, omitting the semicolon also works. (but not in Firefox as of 2016-10-27)

{"x":3, "y":4}
browser console js object syntax error ff 20161027
Common Error when using brower to evaluate a JavaScript object. Firefox Browser, 2016-10-27.
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