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Are tuples more efficient than lists in Python?
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Err, just that the same bytecode is generated absolutely does not mean the same operations happen at the C (and therefore cpu) level. Try creating a class ListLike with a __getitem__ that does something horribly slow, then disassemble x = ListLike((1, 2, 3, 4, 5)); y = x[2]. The by...
Importance of varchar length in MySQL table
...ed dynamically. Because I can not be certain of the length of strings and do not want them cut off, I make them varchar(200) which is generally much bigger than I need. Is there a big performance hit in giving a varchar field much more length than necessary?
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Call a stored procedure with parameter in c#
I can do a delete, insert and update in my program and I try to do an insert by call a created stored procedure from my database.
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What's the best way to share data between activities?
... like to be able to use the data from the first activity.
Now I know I can do something like this:
14 Answers
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Create array of regex matches
...current group state.
For example you can write a lazy iterator to let you do
for (MatchResult match : allMatches(pattern, input)) {
// Use match, and maybe break without doing the work to find all possible matches.
}
by doing something like this:
public static Iterable<MatchResult> allM...
What is tail recursion?
...t starting to learn lisp, I've come across the term tail-recursive . What does it mean exactly?
28 Answers
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How to delete an item in a list if it exists?
...avored constructs are considered a little alien in Python. Around 2005, Guido was even talking about dropping filter - along with companions map and reduce (they are not gone yet but reduce was moved into the functools module, which is worth a look if you like high order functions).
4) Mathematica...
How to find memory leak in a C++ code/project?
I am a C++ programmer on the Windows platform. I am using Visual Studio 2008.
19 Answers
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Handling warning for possible multiple enumeration of IEnumerable
...ble as a parameter is that it tells callers "I wish to enumerate this". It doesn't tell them how many times you wish to enumerate.
I can change the objects parameter to be List and then avoid the possible multiple enumeration but then I don't get the highest object that I can handle.
The goal...
Forward declaration of a typedef in C++
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You can do forward typedef. But to do
typedef A B;
you must first forward declare A:
class A;
typedef A B;
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