0 == false == ""

[Tim Streater]

(e-mail address removed) (Arnaud Diederen

That's very PointedEars of you, Thomas (I know it doesn't actually
mean anything, but those who have read your prose will probably
understand it anyway).


It's not so much a matter of "what's true and what's false" (*) as
it a matter of " *how do you get* to those values", and that...

Try writing "true" or "false" as required.

 

[David Mark]

Randy Webb wrote:
Thomas 'PointedEars' Lahn said the following on 1/15/2008 11:13 PM:
Java script Dude wrote:
[...] When I test both Firefox and IE, they both say ""==false

 

[David Mark]

 (e-mail address removed) (Arnaud Diederen

Try writing "true" or "false" as required.

Required by whom?

 

[Thomas 'PointedEars' Lahn]

Anyone doing a type conversion of string to boolean needs a good smack.

Anyone making such a statement has no clue what they are talking about.

Besides, all generalizations are false ;-)


PointedEars

 

[Arnaud Diederen]

 (e-mail address removed) (Arnaud Diederen







Required by whom?

I don't get it either.

A.

 

[Tim Streater]

(e-mail address removed) (Arnaud Diederen

I don't get it either.

By whoever wants to get to the value, is what I meant.

 

[Tim Streater]

Anyone making such a statement has no clue what they are talking about.

Besides, all generalizations are false ;-)

You mean - the string I typed in evaluates to "false" ??

Damn.

 

[Douglas Crockford]

You should use it only when it is needed.

Too often I see things like this:

typeof o === 'object'

This makes no sense as a typeof operation evaluates to a string
(comparing two strings doesn't involve implicit type conversion.)

However, for example, if a function's argument x can be a string or
null, then strict comparison would be the way to test it:

x === null

If you used a loose comparison on an empty string, you would get the
wrong result.

I think you should use the operator that always gives the right result,
and never use the operator that sometimes gives the wrong result.

http://javascript.crockford.com/

 

[David Mark]

I think you should use the operator that always gives the right result,
and never use the operator that sometimes gives the wrong result.

For the first example, the == operator will always give the right
result. For the second it will not. I don't see any benefit in using
the === operator for everything. To me it makes the code's intentions
less clear.