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Difference between and
...rge downfall of using button types... the form onsubmit event is NOT fired from javascript submissions, leading to potential maintenance nightmares.
– mothmonsterman
Nov 19 '10 at 17:19
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How do I use itertools.groupby()?
...eturns iterators.
Here's an example of that, using clearer variable names:
from itertools import groupby
things = [("animal", "bear"), ("animal", "duck"), ("plant", "cactus"), ("vehicle", "speed boat"), ("vehicle", "school bus")]
for key, group in groupby(things, lambda x: x[0]):
for thing in ...
Why use prefixes on member variables in C++ classes
...ably the most important case is "p" for pointer (because the usage changes from var. to var-> and you have to be much more careful with pointers - NULLs, pointer arithmetic, etc), but all the others are very handy.
For example, you can use the same variable name in multiple ways in a single func...
When to choose mouseover() and hover() function?
...
From the official jQuery documentation
.mouseover()
Bind an event handler to the "mouseover" JavaScript event, or trigger
that event on an element.
.hover() Bind one or two handlers
to the matched elements, to be exe...
In where shall I use isset() and !empty()
...e isset() is not an effective way to validate text inputs and text boxes from a HTML form.
17 Answers
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Is there a difference between “==” and “is”?
...mentation.
Use cases for is include:
None
enum values (when using Enums from the enum module)
usually modules
usually class objects resulting from class definitions
usually function objects resulting from function definitions
anything else that should only exist once in memory (all singletons, ge...
What is the difference between a heuristic and an algorithm?
...ned. The solution could or could not be the best possible one but you know from the start what kind of result you will get. You implement the algorithm using some programming language to get (a part of) a program.
Now, some problems are hard and you may not be able to get an acceptable solution in ...
Reading large text files with streams in C#
... a case where streaming a large, generated CSV file to the Response stream from an ASP.Net MVC action was very slow. Adding a BufferedStream improved performance by 100x in this instance. For more see Unbuffered Output Very Slow
...
Functional programming - is immutability expensive? [closed]
...nsider this reference implementation in Haskell (I don’t know Scala …) from the Haskell introduction:
qsort [] = []
qsort (x:xs) = qsort lesser ++ [x] ++ qsort greater
where lesser = (filter (< x) xs)
greater = (filter (>= x) xs)
The first disadvantage is the choice ...
Read file line by line using ifstream in C++
...
Use ifstream to read data from a file:
std::ifstream input( "filename.ext" );
If you really need to read line by line, then do this:
for( std::string line; getline( input, line ); )
{
...for each line in input...
}
But you probably just need...