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How can you determine a point is between two other points on a line segment?
Let's say you have a two dimensional plane with 2 points (called a and b) on it represented by an x integer and a y integer for each point.
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When to use self over $this?
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$x = new Y();
$x->bar();
?>
The idea is that $this->foo() calls the foo() member function of whatever is the exact type of the current object. If the object is of type X, it thus calls X::foo(). If the object is of type Y, it calls Y::foo(). But with self::foo(), X::foo() is always ...
What's the use of ob_start() in php?
...Think of ob_start() as saying "Start remembering everything that would normally be outputted, but don't quite do anything with it yet."
For example:
ob_start();
echo("Hello there!"); //would normally get printed to the screen/output to browser
$output = ob_get_contents();
ob_end_clean();
There a...
Test if a variable is a list or tuple
... excludes custom sequences, iterators, and other things that you might actually need. However, sometimes you need to behave differently if someone, for instance, passes a string. My preference there would be to explicitly check for str or unicode like so:
import types
isinstance(var, types.String...
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...
How to remove non-alphanumeric characters?
I need to remove all characters from a string which aren't in a-z A-Z 0-9 set or are not spaces.
9 Answers
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SQL Server - copy stored procedures from one db to another
...you tick the top-level checkbox beside "Stored Procedures" it selects them all together - 1 click.
– Barry Kaye
May 22 '12 at 14:06
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show 4...
MySQL, Check if a column exists in a table with SQL
...pecific column, and if not — create it. Otherwise do nothing. This is really an easy procedure in any enterprise-class database, yet MySQL seems to be an exception.
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Why does Windows64 use a different calling convention from all other OSes on x86-64?
AMD has an ABI specification that describes the calling convention to use on x86-64. All OSes follow it, except for Windows which has it's own x86-64 calling convention. Why?
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How can I view all the git repositories on my machine?
Is there a way in which I can see all the git repositories that exist on my machine? Any command for that?
10 Answers
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