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UIViewController viewDidLoad vs. viewWillAppear: What is the proper division of labor?
...pushed, viewWillAppear is called. If you push another subview from there, and the user returns, viewWillAppear is called again.
– Kendall Helmstetter Gelner
Oct 16 '09 at 19:52
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All falsey values in JavaScript
...ing that they evaluate as false in expressions like if(value) , value ? and !value ?
4 Answers
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Is REST DELETE really idempotent?
...quests is the same as for a single
request. The methods GET, HEAD, PUT
and DELETE share this property. Also,
the methods OPTIONS and TRACE SHOULD
NOT have side effects, and so are
inherently idempotent. "
The key bit there is the side-effects of N > 0 identical requests is the same a...
Assigning a variable NaN in python without numpy
...r all comparisons returning false for IEEE754 NaN values? for more details and information.
Instead, use math.isnan(...) if you need to determine if a value is NaN or not.
Furthermore, the exact semantics of the == operation on NaN value may cause subtle issues when trying to store NaN inside con...
how to provide a swap function for my class?
...is the proper use of swap. Write it this way when you write "library" code and want to enable ADL (argument-dependent lookup) on swap. Also, this has nothing to do with SFINAE.
// some algorithm in your code
template<class T>
void foo(T& lhs, T& rhs) {
using std::swap; // enable '...
Should I use document.createDocumentFragment or document.createElement
I was reading about document fragments and DOM reflow and wondered how document.createDocumentFragment differed from document.createElement as it looks like neither of them exist in the DOM until I append them to a DOM element.
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NameError: global name 'unicode' is not defined - in Python 3
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If you need to have the script keep working on python2 and 3 as I did, this might help someone
import sys
if sys.version_info[0] >= 3:
unicode = str
and can then just do for example
foo = unicode.lower(foo)
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Increment a value in Postgres
... want to take a value (which is an integer) in a field in a postgres table and increment it by one. For example if the table 'totals' had 2 columns, 'name' and 'total', and Bill had a total of 203, what would be the SQL statement I'd use in order to move Bill's total to 204?
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What are the differences between Clojure, Scheme/Racket and Common Lisp?
...ew, if possible, covering topics such as syntax, characteristics, features and resources.
4 Answers
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Is Chrome's JavaScript console lazy about evaluating arrays?
...!)
There appears to be some debate regarding just how much of a bug it is and whether it's fixable. It does seem like bad behavior to me. It was especially troubling to me because, in Chrome at least, it occurs when the code resides in scripts that are executed immediately (before the page is loa...