584082 - Narcissus: eliminate uses of ==

Status: RESOLVED FIXED

(Other Applications Graveyard :: Narcissus, defect)

Description

[Dave Herman [:dherman]]

We should use ===, which is clearer and less error-masking than ==, everywhere in the Narcissus codebase.

Dave

Comment 1

[Brendan Eich [:brendan]]

Channeling crock, or just running JSLint?

I intentionally use == where types are the same, since it's equivalent to ===. But maybe this is too fragile -- is there a bug?

/be

Comment 2

[Dave Herman [:dherman]]

I agree with crock on this one, but not necessarily because it lets me tut-tut about JavaScript. It's just that, if we aren't using the extra functionality of ==, it's misleading to the reader -- why use the more powerful operation when you aren't using its power? Principle of least power or whatever you call it.

Dave

Comment 3

[Brendan Eich [:brendan]]

(South Park voice:) They got Dave -- bastards!

;-)

/be

Comment 4

[Dave Herman [:dherman]]

I'll take the ribbing, but seriously: DWIM is rarely WIM, and if you don't even intend to be using it, you're taking the risk of silently masking bugs. No need to raise the spooky spectre of security, it's just better preparation for when bugs happen.

Dave

Comment 5

[Dave Herman [:dherman]]

Attachment: eliminates uses of ==

This patch eliminates all uses of == and != except for the part where the evaluator is interpreting those operators. There's a spot where the original code used |== null| to check for either null or undefined, and I've replaced that with the more explicit two checks, using ===.

Dave

Comment 6

[Patrick Walton (:pcwalton)]

r=me

Note that I prefer "foo == null" to "foo === null || foo === undefined", but I don't have really strong opinions either way.

Comment 7

[Dave Herman [:dherman]]

http://hg.mozilla.org/tracemonkey/rev/015059c45596

Comment 8

[Brendan Eich [:brendan]]

(In reply to comment #6)
> r=me
> 
> Note that I prefer "foo == null" to "foo === null || foo === undefined", but I
> don't have really strong opinions either way.

Yeah, this is another case where I used == intentionally (and still will in my own JS hacking). Slightly more economical and efficient, but maybe confusing to JS hackers who don't know the mysteries of ==, or who would prefer to forget.

/be

Comment 9

[Shu-yu Guo [:shu]]

Attachment: Missed one test in jsexec

Comment 10

[Shu-yu Guo [:shu]]

Missed one! Patch attached.

Comment 11

[Brendan Eich [:brendan]]

Best to file a followup bug, or just fix it without a bug if you are cheeky. Reopening when there was not a back-out makes for a confusing audit trail.

/be

Comment 12

[Shu-yu Guo [:shu]]

Sorry, didn't know about that protocol. WIll open a new bug.