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List changes unexpectedly after assignment. How do I clone or copy it to prevent this?
...
With new_list = my_list, you don't actually have two lists. The assignment just copies the reference to the list, not the actual list, so both new_list and my_list refer to the same list after the assignment.
To actually copy the list, you have various possibilit...
MySQL query String contains
...
Quite simple actually:
mysql_query("
SELECT *
FROM `table`
WHERE `column` LIKE '%{$needle}%'
");
The % is a wildcard for any characters set (none, one or many). Do note that this can get slow on very large datasets so if your database grow...
How do you express binary literals in Python?
... memory.
Note that leading zeros in a non-zero decimal number are not allowed.
This is for disambiguation with C-style octal literals, which Python
used before version 3.0.
Some examples of integer literals:
7 2147483647 0o177 0b100110111
3 7922816251...
What is a stream?
...
A stream represents a sequence of objects (usually bytes, but not necessarily so), which can be accessed in sequential order. Typical operations on a stream:
read one byte. Next time you read, you'll get the next byte, and so on.
read several bytes from the stream into...
Looking to understand the iOS UIViewController lifecycle
...
All these commands are called automatically at the appropriate times by iOS when you load/present/hide the view controller. It's important to note that these methods are attached to UIViewController and not to UIViews themsel...
In where shall I use isset() and !empty()
... it's not a good idea to use this operator for math in case "0" is accidentally a string. This can be dangerous. Instead, use basic >, < and == operators and convert variables using intval() or floatval().
– kaleazy
Feb 14 at 18:08
...
How to save an HTML5 Canvas as an image on a server?
I'm working on a generative art project where I would like to allow users to save the resulting images from an algorithm. The general idea is:
...
Getting the caller function name inside another function in Python? [duplicate]
...on 2 each frame record is a list. The third element in each record is the caller name. What you want is this:
>>> import inspect
>>> def f():
... print inspect.stack()[1][3]
...
>>> def g():
... f()
...
>>> g()
g
For Python 3.5+, each frame record i...
Overriding fields or properties in subclasses
...his is how a truly polymorphic implementation of your property might look, allowing the derived classes to be in control.
abstract class Parent
{
abstract public int MyInt { get; }
}
class Father : Parent
{
public override int MyInt
{
get { /* Apply formula "X" and return a val...
Convert a Scala list to a tuple?
...e of Scala sequence using the +: syntax. Also, don't forget to add a catch-all
– ig-dev
Jun 19 '19 at 8:33
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