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Nested classes' scope?
...e found in Python Documentation The Python Tutorial
For your first error <type 'exceptions.NameError'>: name 'outer_var' is not defined. The explanation is:
There is no shorthand for referencing data attributes (or other methods!) from within methods. I find that this actually increases t...
Should I declare Jackson's ObjectMapper as a static field?
...
Although ObjectMapper is thread safe, I would strongly discourage from declaring it as a static variable, especially in multithreaded application.
Not even because it is a bad practice, but because you are running a heavy risk...
How to build query string with Javascript
Just wondering if there is anything built-in to Javascript that can take a Form and return the query parameters, eg: "var1=value&var2=value2&arr[]=foo&arr[]=bar..."
...
Rails 4 - Strong Parameters - Nested Objects
...:type, :coordinates => []])
On the other hand if you want nested of multiple objects then you wrap it inside a hash… like this
params.require(:foo).permit(:bar, {:baz => [:x, :y]})
Rails actually have pretty good documentation on this: http://api.rubyonrails.org/classes/ActionControll...
How to get a variable name as a string in PHP?
...r but I came up with this. It works, for the limited uses below.
shrug
<?php
function varName( $v ) {
$trace = debug_backtrace();
$vLine = file( __FILE__ );
$fLine = $vLine[ $trace[0]['line'] - 1 ];
preg_match( "#\\$(\w+)#", $fLine, $match );
print_r( $match );
}
$foo = "...
get the latest fragment in backstack
...fore, a valid solution would be:
public Fragment getTopFragment() {
List<Fragment> fragentList = fragmentManager.getFragments();
Fragment top = null;
for (int i = fragentList.size() -1; i>=0 ; i--) {
top = (Fragment) fragentList.get(i);
if (top != null) {
return top;
...
Is Meyers' implementation of the Singleton pattern thread safe?
...l placement new on s to construct it
}
return (*(reinterpret_cast<Singleton*>( &s)));
}
So here's a simple thread-safe Singleton (for Windows). It uses a simple class wrapper for the Windows CRITICAL_SECTION object so that we can have the compiler automatically initialize the C...
Mercurial: how to amend the last commit?
...on 2 (2) Remove "file" and have some other changes (3) Commit changes, resulting in revision 3 (4) Now I'll change my mind and decide "file" should not be removed from the commit, so I want to amend revision 3. Hence, I'll re-add "file" which is now unversioned (5) Now I perform rollback: it will re...
Given a view, how do I get its viewController?
...ore or set the next responder automatically, instead returning nil by default. Subclasses must override this method to set the next responder. UIView implements this method by returning the UIViewController object that manages it (if it has one) or its superview (if it doesn’t); UIViewController i...
How to output only captured groups with sed?
...^[:digit:]]+([[:digit:]]+)[^[:digit:]]*/\1 \2/p'
This says:
don't default to printing each line (-n)
exclude zero or more non-digits
include one or more digits
exclude one or more non-digits
include one or more digits
exclude zero or more non-digits
print the substitution (p)
In general, in se...