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Is the practice of returning a C++ reference variable evil?
...
In general, returning a reference is perfectly normal and happens all the time.
If you mean:
int& getInt() {
int i;
return i; // DON'T DO THIS.
}
That is all sorts of evil. The stack-allocated i will go away and you are referring to nothing. This is also evil:
int& get...
Python None comparison: should I use “is” or ==?
...ject None, so when you do my_var is None, you're checking whether they actually are the same object (not just equivalent objects)
In other words, == is a check for equivalence (which is defined from object to object) whereas is checks for object identity:
lst = [1,2,3]
lst == lst[:] # This is Tr...
How do I size a UITextView to its content?
... Tested on iOS 7 to resize an UITextView into an UITableViewCell. Works really great. This is the only answer that finally worked for me. Thanks!
– Alex
Nov 30 '13 at 18:40
39
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How to deep copy a list?
... don't make a deep copy using list() (Both list(...) and testList[:] are shallow copies).
You use copy.deepcopy(...) for deep copying a list.
deepcopy(x, memo=None, _nil=[])
Deep copy operation on arbitrary Python objects.
See the following snippet -
>>> a = [[1, 2, 3], [4, 5, 6]]...
What's the (hidden) cost of Scala's lazy val?
...nswered Jun 15 '10 at 7:51
oxbow_lakesoxbow_lakes
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KIO4_Gradient 拓展：布局中的颜色渐变 - App Inventor 2 中文网 - 清泛IT...
http://kio4.com/appinventor/287_extension_gradiente_color.htm
- 让我们看一下在布局中制作颜色渐变的扩展。- 我们放置一个布局，然后在该扩展的块中插入该布局的名称，放置一个包含所需颜色的列表，以及一个从 1 到 8 的数字，用于表示...
Hidden features of Perl?
What are some really useful but esoteric language features in Perl that you've actually been able to employ to do useful work?
...
Android OpenGL ES and 2D
...ur canvas with the proper GL flags for 2D (sprite) rendering.
You should really take a look at SpriteMethodTest by the same author of replica island: http://code.google.com/p/apps-for-android/source/browse/trunk/SpriteMethodTest
See this question where I posted my own code: Using OpenGL to replace ...
How to use pull to refresh in Swift?
...lf.tableView.reloadData() and self.refreshControl?.endRefreshing() in the callback?
– Qian Chen
Dec 6 '15 at 19:58
Exa...
Check if a value is within a range of numbers
...u're asking a question about numeric comparisons, so regular expressions really have nothing to do with the issue. You don't need "multiple if" statements to do it, either:
if (x >= 0.001 && x <= 0.009) {
// something
}
You could write yourself a "between()" function:
function b...