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What is the difference between a mutable and immutable string in C#?
...to make a copy of it if you want to be absolutely sure it won't change out from under you. This is why mutable objects are dangerous to use as keys into any form of Dictionary or set- the objects themselves could change, and the data structure would have no way of knowing, leading to corrupt data th...
Can someone explain the “debounce” function in Javascript
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The code in the question was altered slightly from the code in the link. In the link, there is a check for (immediate && !timeout) BEFORE creating a new timout. Having it after causes immediate mode to never fire. I have updated my answer to annotate the working ...
Serializing an object to JSON
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Just to keep it backward compatible I load Crockfords JSON-library from cloudflare CDN if no native JSON support is given (for simplicity using jQuery):
function winHasJSON(){
json_data = JSON.stringify(obj);
// ... (do stuff with json_data)
}
if(typeof JSON === 'object' && type...
GetManifestResourceStream returns NULL
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You can check that the resources are correctly embedded by using
//From the assembly where this code lives!
this.GetType().Assembly.GetManifestResourceNames()
//or from the entry point to the application - there is a difference!
Assembly.GetExecutingAssembly().GetManifestResourceNames()
w...
Can I use if (pointer) instead of if (pointer != NULL)?
...verted into boolean false while non-null pointers are converted into true. From the C++11 standard, section on Boolean Conversions:
A prvalue of arithmetic, unscoped enumeration, pointer, or pointer to member type can be converted to a
prvalue of type
bool. A zero value, null pointer value, ...
Getting number of elements in an iterator in Python
...g the iterator. One of probably the most efficient ways:
import itertools
from collections import deque
def count_iter_items(iterable):
"""
Consume an iterable not reading it into memory; return the number of items.
"""
counter = itertools.count()
deque(itertools.izip(iterable,...
Is recursion ever faster than looping?
...n some environments these functions are the first (or only) to get a boost from automatic parallelization — so they can be significantly faster than either iteration or recursion. Data Parallel Haskell is an example of such an environment.
List comprehensions are another alternative, but these ...
Entity Framework code first unique column
...he 900-byte limit for the maximum total size of all index key columns."
(from: http://msdn.microsoft.com/en-us/library/ms191241.aspx )
You can solve this by setting a maximum string length on your model:
[StringLength(450)]
Your model will look like this now in EF CF 6.1+:
public class User
{...
Is “else if” faster than “switch() case”? [duplicate]
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From my point of view switch is also far more readable than if-elseif chain. which is also prone to errors such as mixing up if-else; if-else; in it which has other side effects. with switch you see n-fork right away, while w...
Printing HashMap In Java
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keySet() only returns a set of keys from your hashmap, you should iterate this key set and the get the value from the hashmap using these keys.
In your example, the type of the hashmap's key is TypeKey, but you specified TypeValue in your generic for-loop, so...