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Why do I have to access template base class members through the this pointer?
...re not templates I could simply have x in the derived class. However, with the code below, I have to use this->x . Why?
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How to check if a variable is not null?
...owing the if statement if myVar is truthy (i.e. evaluates to true in a conditional), while the second will execute the block if myVar is any value other than null.
The only values that are not truthy in JavaScript are the following (a.k.a. falsy values):
null
undefined
0
"" (the empty string)
fal...
Which is faster: Stack allocation or Heap allocation
This question may sound fairly elementary, but this is a debate I had with another developer I work with.
23 Answers
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How unique is UUID?
How safe is it to use UUID to uniquely identify something (I'm using it for files uploaded to the server)? As I understand it, it is based off random numbers. However, it seems to me that given enough time, it would eventually repeat it self, just by pure chance. Is there a better system or a patter...
Why is document.write considered a “bad practice”?
I know document.write is considered bad practice; and I'm hoping to compile a list of reasons to submit to a 3rd party vendor as to why they shouldn't use document.write in implementations of their analytics code.
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Why is this inline-block element pushed downward?
...ers. I really want to understand the inner workings of the fact that why its being pushed downward rather than pulling it upward by one way or another. (and I know how to align their tops :))
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What is this weird colon-member (“ : ”) syntax in the constructor?
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It's a member initialization list. You should find information about it in any good C++ book.
You should, in most cases, initialize all member objects in the member initialization list (however, do note the exceptions liste...
PostgreSQL: Difference between text and varchar (character varying)
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There is no difference, under the hood it's all varlena (variable length array).
Check this article from Depesz: http://www.depesz.com/index.php/2010/03/02/charx-vs-varcharx-vs-varchar-vs-text/
A couple of highlights:
To sum it all up:
char(n) – ta...
Running Bash commands in Python
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Don't use os.system. It has been deprecated in favor of subprocess. From the docs: "This module intends to replace several older modules and functions: os.system, os.spawn".
Like in your case:
bashCommand = "cwm --rdf test.rdf --ntriples > t...
Convert a PHP script into a stand-alone windows executable
I want to automate a fairly simple task. For this I have written a small PHP script which I run from the command line using PHP-CLI. Now I want to hand over this script to someone but I do not want to:
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