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Reference: What is variable scope, which variables are accessible from where and what are “undefined
... be in the global scope in a.php doesn't necessarily mean they are, it actually depends on which context that code is included/executed in.
What about functions inside functions and classes?
Every new function declaration introduces a new scope, it's that simple.
(anonymous) functions inside func...
What is the purpose of the single underscore “_” variable in Python?
...cate that part
of a function result is being deliberately ignored (Conceptually, it is being discarded.), as in code like:
label, has_label, _ = text.partition(':').
As part of a function definition (using either def or lambda), where
the signature is fixed (e.g. by a callback or parent class API), ...
How to downgrade or install an older version of Cocoapods
How can I downgrade Cocoapods to an older version, or how can I install an older version of Cocoapods?
6 Answers
...
Escaping regex string
...this:
4.2.3 re Module Contents
escape(string)
Return string with all non-alphanumerics backslashed; this is useful if you want to match an arbitrary literal string that may have regular expression metacharacters in it.
A simplistic example, search any occurence of the provided string opt...
How are GCC and g++ bootstrapped?
...ilt
(optional) repeat step 2 for verification purposes.
This process is called bootstrapping. It tests the compiler's capability of compiling itself and makes sure that the resulting compiler is built with all the optimizations that it itself implements.
EDIT: Drew Dormann, in the comments, point...
Kill child process when parent process is killed
...plication dies, you are still left with child processes running. What we really want is for the child processes to die as soon as the main process dies.
The solution is to use "job objects" http://msdn.microsoft.com/en-us/library/ms682409(VS.85).aspx.
The idea is to create a "job object" for your ...
What is the _snowman param in Ruby on Rails 3 forms for?
...net Explorer (5, 6, 7 and 8) to encode its parameters as unicode.
Specifically, this bug can be triggered if the user switches the browser's encoding to Latin-1. To understand why a user would decide to do something seemingly so crazy, check out this google search. Once the user has put the web-sit...
How do I add multiple arguments to my custom template filter in a django template?
...
It is possible and fairly simple.
Django only allows one argument to your filter, but there's no reason you can't put all your arguments into a single string using a comma to separate them.
So for example, if you want a filter that checks if variable X is in the list [1...
Why does GCC generate such radically different assembly for nearly the same C code?
...e(). I'll spare you the assembly, but it is identical - register names and all.
Step 2: Mathematical reduction: x + (y ^ x) = y
sign can only take one of two values, 0 or 0x80000000.
When x = 0, then x + (y ^ x) = y then trivial holds.
Adding and xoring by 0x80000000 is the same. It flips the sign...
What algorithm does Readability use for extracting text from URLs?
... the "relevant" text from a URL by eliminating the text related to ads and all the other clutter.After several months of researching, I gave it up as a problem that cannot be accurately determined. (I've tried different ways but none were reliable)
...