719616 - Display warning in the error console when handlers like onclick, onmousedown etc. get passed something else than a function

Status: NEW

(Core :: DOM: Events, enhancement, P5)

Description

[Tobias (:Tobbi) Markus]

Now, this is something I encountered while debugging a script from another guy (JavaScript beginner). This is what he wrote:
document.getElementsByTagName('input')[0].onclick='displayPage2()'. 

You can clearly see that this is not a function call, but a string containing the function call gets passed to onclick. The problem is that this fails silently, no errors in the error console get shown.

Would it be possible to display a small warning in the error console that states that there was something else than a function passed to an on... handler? It would ease learning JS for beginners.

Comment 1

[Firefox Bug Husbandry Bot]

https://bugzilla.mozilla.org/show_bug.cgi?id=1472046

Move all DOM bugs that haven’t been updated in more than 3 years and has no one currently assigned to P5.

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