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How to initialize private static members in C++?
... should be in the header file (Or in the source file if not shared).
File: foo.h
class foo
{
private:
static int i;
};
But the initialization should be in source file.
File: foo.cpp
int foo::i = 0;
If the initialization is in the header file then each file that includes the header ...
How to create a self-signed certificate for a domain name for development?
...'t know why this answer has so many upvotes?
– c00000fd
Sep 23 '15 at 20:41
25
This gets upvotes ...
Inheriting class methods from modules / mixins in Ruby
...idiom is to use included hook and inject class methods from there.
module Foo
def self.included base
base.send :include, InstanceMethods
base.extend ClassMethods
end
module InstanceMethods
def bar1
'bar1'
end
end
module ClassMethods
def bar2
'bar2'
en...
Error: “dictionary update sequence element #0 has length 1; 2 is required” on Django 1.4
...stance, the following functions throw the error from the question:
url(r'^foo/(?P<bar>[A-Za-z]+)/$', views.FooBar.as_view(), 'foo')
path('foo/{slug:bar}/', views.FooBar, 'foo')
But these actually work:
url(r'^foo/(?P<bar>[A-Za-z]+)/$', views.FooBar.as_view(), name='foo')
path('foo/{s...
How to tell if a string is not defined in a Bash shell script
...
~> if [ -z $FOO ]; then echo "EMPTY"; fi
EMPTY
~> FOO=""
~> if [ -z $FOO ]; then echo "EMPTY"; fi
EMPTY
~> FOO="a"
~> if [ -z $FOO ]; then echo "EMPTY"; fi
~>
-z works for undefined variables too. To distinguish between...
What are some examples of commonly used practices for naming git branches? [closed]
...roup tokens
Use "grouping" tokens in front of your branch names.
group1/foo
group2/foo
group1/bar
group2/bar
group3/bar
group1/baz
The groups can be named whatever you like to match your workflow. I like to use short nouns for mine. Read on for more clarity.
Short well-defined tokens
Choose...
variable === undefined vs. typeof variable === “undefined”
...
For undeclared variables, typeof foo will return the string literal "undefined", whereas the identity check foo === undefined would trigger the error "foo is not defined".
For local variables (which you know are declared somewhere), no such error would occu...
How to pipe stdout while keeping it on screen ? (and not to a output file)
...on some non Unix environments like cygwin too.
echo 'ee' | tee /dev/tty | foo
Reference: The Open Group Base Specifications Issue 7
IEEE Std 1003.1, 2013 Edition, §10.1:
/dev/tty
Associated with the process group of that process, if any. It is
useful for programs or shell procedures ...
Understanding PrimeFaces process/update and JSF f:ajax execute/render attributes
...certain command component is invoked ain't gonna work:
<p:inputText id="foo" value="#{bean.foo}" />
<p:commandButton process="foo" action="#{bean.action}" />
It would only process the #{bean.foo} and not the #{bean.action}. You'd need to include the command component itself as well:
<...
How to return a string value from a Bash function
... return.
#!/bin/bash
set -x
function pass_back_a_string() {
eval "$1='foo bar rab oof'"
}
return_var=''
pass_back_a_string return_var
echo $return_var
Prints "foo bar rab oof".
Edit: added quoting in the appropriate place to allow whitespace in string to address @Luca Borrione's comment.
E...