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Double not (!!) operator in PHP
...ings or empty arrays) you will get the boolean value FALSE.
It is functionally equivalent to a cast to boolean:
return (bool)$row;
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Reading a huge .csv file
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You are reading all rows into a list, then processing that list. Don't do that.
Process your rows as you produce them. If you need to filter the data first, use a generator function:
import csv
def getstuff(filename, criterion):
with ...
Super-simple example of C# observer/observable with delegates
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The observer pattern is usually implemented with events.
Here's an example:
using System;
class Observable
{
public event EventHandler SomethingHappened;
public void DoSomething() =>
SomethingHappened?.Invoke(this, EventArgs.Empt...
Is there a way to make mv create the directory to be moved to if it doesn't exist?
...ectories don't exist, is there some way to have those directories automatically created, so that you would only have to type
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Maven command to list lifecycle phases along with bound goals?
...n wrong, but this command is the "reverse lookup" to the question (Listing all phases this goal is in)? link says "Displays a list of the attributes for a Maven Plugin and/or goals (aka Mojo - Maven plain Old Java Object)."
– user2039709
Nov 17 '16 at 13:45
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Add custom messages in assert?
...rk; they’re compile-time constants and their use in this context is trivially optimized away. There is no runtime cost.
– zneak
Aug 9 '19 at 8:46
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Is there a difference between foo(void) and foo() in C++ or C?
...tion across both languages and make our headers multilingual (though we usually need to do some more things to the headers to make them truly cross-language; namely, wrap them in an extern "C" if we're compiling C++).
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Practical use of `stackalloc` keyword
Has anyone ever actually used stackalloc while programming in C#? I am aware of what is does, but the only time it shows up in my code is by accident, because Intellisense suggests it when I start typing static , for example.
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What are the git concepts of HEAD, master, origin?
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I highly recommend the book "Pro Git" by Scott Chacon. Take time and really read it, while exploring an actual git repo as you do.
HEAD: the current commit your repo is on. Most of the time HEAD points to the latest commit in your current branch, but that doesn't have to be the case. HEAD rea...
M_PI works with math.h but not with cmath in Visual Studio
...) and suddenly it compile perfectly.
Try moving it higher up the page. Totally unsure as to why this would cause issues though.
Edit: Figured it out. The #include <math.h> occurs within cmath's header guards. This means that something higher up the list of #includes is including cmath with...