known about this for awhile but since we are on the topic... there has to be some over head of using == and !=.... does anyone know for sure the impact of the overhead... and does it matter of the type....
On Aug 2, 6:21 am, "Ian Struble" <[EMAIL PROTECTED]> wrote: > !== and === are identity operators. It is a good idea to use them > instead of the equality operators (!= and ==) unless you know why you > would want to use equality (and the possible type coercion) over > identity. Probably the biggest gotcha with equality is with falsy > values (false, 0, undefined, ""/empty string, null and NaN). The > truthy / falsy issue is probably what bit you Rob. > > It may be worth reading a bit of Douglas Crockford's ideas about > javascript if you are trying to figure out identity and equality > operators: > > http://javascript.crockford.com/code.html > > And here is something about truthy and falsy: > > http://developer.mozilla.org/en/docs/A_re-introduction_to_JavaScript#... > > Ian > > On 8/2/07, Rob Desbois <[EMAIL PROTECTED]> wrote: > > > I had a discussion on the use of the === and !== operators recently on this > > list, my opinion was, and still is, that unless you explicitly WANT to allow > > type conversion, you should be using these. Only use == and != if you really > > want type conversion. > > > It's bitten me once, although I can't for the life of me remember how, but > > it involved lots of in-depth debugging and head-scratching to find the > > problem. I'm more wary now and think that these operators are the way to go. > > > --rob > > > On 8/2/07, Sam Collett <[EMAIL PROTECTED]> wrote: > > > > I don't think many actually use !== (and when you would want to use > > > it) and many sites that show usage of operators don't cover !== (but > > > do have ===). > > > > 3 != '3' false > > > 3 !== '3' true > > > 3 == '3' true > > > 3 === '3' false > > > > On Aug 1, 9:33 pm, "Michael Geary" <[EMAIL PROTECTED]> wrote: > > > > > I...cannot figure how what the heck === is. > > > > > I see that Jake answered your question, but just for next time... > > > > > You may have tried a Google search for "javascript ===" and been > > > > disappointed to find it returned no useful results (because Google seems > > to > > > > ignore the === in the search). > > > > > The key thing to know is that ===, like most special symbols in > > JavaScript > > > > such as + and -, is an operator. Now you can do a more productive Google > > > > search: > > > > >http://www.google.com/search?q=javascript+operators > > > > > This will help when you run into !== and wonder what the heck *that* one > > is. > > > > :-) > > > > > -Mike > > > -- > > Rob Desbois > > Eml: [EMAIL PROTECTED] > > Tel: 01452 760631 > > Mob: 07946 705987 > > "There's a whale there's a whale there's a whale fish" he cried, and the > > whale was in full view. > > ...Then ooh welcome. Ahhh. Ooh mug welcome.
