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Why does the lock object have to be static?
... a private static readonly object for locking in multi threading.
I understand that private reduces the entry points to the locking object by tightening the encapsulation and therefore access to the most essential.
...
Do c++11 lambdas capture variables they don't use?
...apture variables that are both (a) not expressly named in the capture list and (b) used in the body of the lambda expression. If a variable is not expressly named and you don't use the variable in the lambda expression, then the variable is not captured. In your example, my_huge_vector is not capt...
How do I determine whether my calculation of pi is accurate?
...record territory, there's nothing to compare against.
Historically, the standard approach for verifying that computed digits are correct is to recompute the digits using a second algorithm. So if either computation goes bad, the digits at the end won't match.
This does typically more than double t...
src/lxml/etree_defs.h:9:31: fatal error: libxml/xmlversion.h: No such file or directory
... Notice for Ubuntu 13.04 users: if you have libxml2 already installed and upgraded to version 2.9.0+dfsg1-4ubuntu4.3 you need to downgrade it to 2.9.0+dfsg1-4ubuntu4.1 by typing the command sudo apt-get install libxml2=2.9.0+dfsg1-4ubuntu4.1 otherwise the libxml2-dev wont be installed due versi...
How can I change an element's class with JavaScript?
...Explorer prior to v10, though there is a shim to add support for it to IE8 and IE9, available from this page. It is, though, getting more and more supported.
Simple cross-browser solution
The standard JavaScript way to select an element is using document.getElementById("Id"), which is what the fol...
Insert a line break in mailto body
I would like to insert a line break into my mailto body.
I tried %0A, %0D and %0D%0A. Nothing worked for me.
I tested on Gmail, Yahoo, Apple Mail, Outlook 2010, Outlook.com and Thunderbird with Google Chrome on Mac OSX.
...
How can I use Bash syntax in Makefile targets?
...sed as the shell.
So put SHELL := /bin/bash at the top of your makefile, and you should be good to go.
BTW: You can also do this for one target, at least for GNU Make. Each target can have its own variable assignments, like this:
all: a b
a:
@echo "a is $$0"
b: SHELL:=/bin/bash # HERE: t...
Why do I get a segmentation fault when writing to a “char *s” initialized with a string literal, but
...r a[] , it specifies the initial values
of the characters in that array (and,
if necessary, its size).
Anywhere else, it turns into an unnamed, static array of characters,
and this unnamed array may be stored
in read-only memory, and which
therefore cannot necessarily be
modified. In a...
How to check if a map contains a key in Go?
...ng here
}
Explanation:
if statements in Go can include both a condition and an initialization statement. The example above uses both:
initializes two variables - val will receive either the value of "foo" from the map or a "zero value" (in this case the empty string) and ok will receive a bool ...
How to add a border just on the top side of a UIView
...
I consider subclassing UIView and overriding drawRect overkill here. Why not add an extension on UIView and add border subviews?
@discardableResult
func addBorders(edges: UIRectEdge,
color: UIColor,
inset: CGFloat = 0.0,
...