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Difference between $(document.body) and $('body')
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Could be resolved now. There was a time when FF and IE would let you do this, and/or would get confused by items with an id of "body" (the error I hit was a customer using our script on a plastic surgeon's site with a picture tagged with the id "body"). Hopefu...
Is it possible to change the package name of an Android app on Google Play?
...t find it on the market.
Not ideal and can be annoying to the users, sometimes even impossible to implement due to the status/possibilities of the app. But since Google left us no choice this is the only way to migrate the users of the old apps to a "new" one (even if it is not really new).
Not to...
PHP best way to MD5 multi-dimensional array?
...i:0;a:1:{i:0;a:1:{i:0;a:0:{}}}}}}}}}');
//The serialize test
$b4_s = microtime(1);
for ($i=0;$i<10000;$i++) {
$serial = md5(serialize($array));
}
echo 'serialize() w/ md5() took: '.($sTime = microtime(1)-$b4_s).' sec<br/>';
//The json test
$b4_j = microtime(1);
for ($i=0;$i<10000;$...
Should I use 'has_key()' or 'in' on Python dicts?
...omputing the hash) and doing a lookup. Note that d.keys() is only about 10 times as long as this, which is still not long really. I haven't checked but I'm still pretty sure it's only O(1).
– Arthur Tacca
Aug 2 '18 at 8:40
...
Why can't yield return appear inside a try block with a catch?
...f practicality rather than feasibility. I suspect there are very, very few times where this restriction is actually an issue that can't be worked around - but the added complexity in the compiler would be very significant.
There are a few things like this that I've already encountered:
Attributes...
What is the difference between ? and Object in Java generics?
... to help me clean up some code to use Java generics properly. Most of the time it's doing an excellent job of inferring types, but there are some cases where the inferred type has to be as generic as possible: Object. But Eclipse seems to be giving me an option to choose between a type of Object a...
Why do you need explicitly have the “self” argument in a Python method?
...en you have variable names that make it impossible to deduce. So you sometimes need it and sometimes don't.
Python elects to make things like this explicit rather than based on a rule.
Additionally, since nothing is implied or assumed, parts of the implementation are exposed. self.__class__, ...
Why doesn't the example compile, aka how does (co-, contra-, and in-) variance work?
...ous, this is bad news. Java's type system actually allows this at compile time. The JVM will "helpfully" throw an ArrayStoreException at runtime. Scala's type system prevents this problem because the type parameter on the Array class is invariant (declaration is [A] rather than [+A]).
Note that ...
Best design for a changelog / auditing database table? [closed]
...very minimalistic design, like the one you described:
event ID
event date/time
event type
user ID
description
The idea was the same: to keep things simple.
However, it quickly became obvious that this minimalistic design was not sufficient. The typical audit was boiling down to questions like t...
What is the difference between null and undefined in JavaScript?
...ll and leave undefined the value for things you forgot to set. At the same time, I really encourage you to always set every variable. JavaScript has a scope chain different than that of C-style languages, easily confusing even veteran programmers, and setting variables to null is the best way to pre...