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Performance surprise with “as” and nullable types
...cient. One rule that really helps there is that an object can only be unboxed to a variable that has the same type as the boxed value. That allows the JIT compiler to generate very efficient code, no value conversions have to be considered.
The is operator test is easy, just check if the object i...
How to get the index of an element in an IEnumerable?
...iterate over the contents. As such, there isn't really a concept of an index. What you are doing really doesn't make a lot of sense for an IEnumerable. If you need something that supports access by index, put it in an actual list or collection.
...
Why does += behave unexpectedly on lists?
The += operator in python seems to be operating unexpectedly on lists. Can anyone tell me what is going on here?
8 Answe...
Purpose of Python's __repr__
...__repr__ is more for developers while __str__ is for end users.
A simple example:
>>> class Point:
... def __init__(self, x, y):
... self.x, self.y = x, y
... def __repr__(self):
... return 'Point(x=%s, y=%s)' % (self.x, self.y)
>>> p = Point(1, 2)
>>> p
Poin...
Declare and initialize a Dictionary in Typescript
...
Edit: This has since been fixed in the latest TS versions. Quoting @Simon_Weaver's comment on the OP's post:
Note: this has since been fixed (not sure which exact TS version). I
get these errors in VS, as you would expect: Index signatures are
i...
How to Apply Gradient to background view of iOS Swift App
...(main view of a storyboard). The code runs, but nothing changes. I'm using xCode Beta 2 and Swift.
30 Answers
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The most efficient way to implement an integer based power function pow(int, int)
...
Exponentiation by squaring.
int ipow(int base, int exp)
{
int result = 1;
for (;;)
{
if (exp & 1)
result *= base;
exp >>= 1;
if (!exp)
break;
base ...
Focus-follows-mouse (plus auto-raise) on Mac OS X
...ine:
defaults write com.apple.Terminal FocusFollowsMouse -bool true
For X11 apps you can do this:
defaults write com.apple.x11 wm_ffm -bool true
In Snow Leopard, use this instead:
defaults write org.x.X11 wm_ffm -bool true
Apparently there's a program called CodeTek Virtual Desktop that'll ...
How can I strip first X characters from string using sed?
I am writing shell script for embedded Linux in a small industrial box. I have a variable containing the text pid: 1234 and I want to strip first X characters from the line, so only 1234 stays. I have more variables I need to "clean", so I need to cut away X first characters and ${string:5} does...
Error - trustAnchors parameter must be non-empty
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