Re: Is jQuery worth a second look?

On Sep 30, 5:06 pm, Oltmans wrote:
On Sep 30, 6:38 pm, "Thomas 'PointedEars' Lahn" wrote:
kangax wrote:
dhtml wrote:
isFunction - still uses function decompilation. Kangax posted on
es-discuss that that was changed but I still see the isFunction in the
latest 1.2.6.

Garrett,
their trunk is using `instanceof` [1].

Irrelevant, except that it shows their cluelessness.

Why using "instanceof" considered to be not so good? Can you
please explain it to me with a few examples? That will be
highly appreciated.

The - instanceof - operator makes assertions about the runtime
relationships between the objects on the prototype chain of one object
and that object that is the value of the - prototype - property of a
(single) function object. Because it is possible, at any time, to
create objects with virtually any other object on their prototype
chain, and to assign to the - prototype - properties of most functions
(though not the built-in constructors) that relationship is only as
meaningful as to can be know to be. It is in the nature of library
code that it has no control over, or knowledge about, the code that
employs it or sits around it, and so no guarantee of the usefulness/
applicability of the relationship being tested.
.

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