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Dictionary returning a default value if the key does not exist [duplicate]
...Value(key, out value);
and just ignore the return value. However, that really will just return default(TValue), not some custom default value (nor, more usefully, the result of executing a delegate). There's nothing more powerful built into the framework. I would suggest two extension methods:
pu...
To ARC or not to ARC? What are the pros and cons? [closed]
...t has no GC runtime overhead. The compiler inserts retains and releases in all the places you should have anyway. But it's smarter than you and can optimize out the ones that aren't actually needed (just like it can unroll loops, eliminate temporary variables, inline functions, etc.)
OK, now I will...
Can I replace groups in Java regex?
I have this code, and I want to know, if I can replace only groups (not all pattern) in Java regex.
Code:
7 Answers
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What breaking changes are introduced in C++11?
...nity, whereas C++0x always rounds the result toward 0.
(admittedly not really a compatibility problem for most people).
Valid C++ 2003 code that uses the keyword auto as a storage class specifier may be invalid in C++0x.
Narrowing conversions cause incompatibilities with C++03. For ex...
Select between two dates with Django
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Use the __range operator:
...filter(current_issue__isnull=True, created_at__range=(start_date, end_date))
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Get a list of distinct values in List
...the Default equality comparer. msdn.microsoft.com/en-us/library/bb348436(v=vs.110).aspx
– Georg Patscheider
Jan 21 '16 at 23:01
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How can I match a string with a regex in Bash?
...ching in the second example. Inside [[ ]], the * is not expanded as it usually is, to match filenames in the current directory that match a pattern.Your example works, but it's really easy to over-generalize and mistakenly believe that * means to match anything in any context. It only works like t...
what is .netrwhist?
...riting files across networks. .netrwhist is a history file which maintains all the directories that were modified. So whenever you modify the contents of ~/.vim it adds one entry in .netrwhist
A sample .netrwhist is as shown
let g:netrw_dirhistmax =10
let g:netrw_dirhist_cnt =6
let g:netrw_dirhis...
When to use inline function and when not to use it?
...at inline is a hint or request to compiler and its used to avoid function call overheads.
14 Answers
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Fundamental difference between Hashing and Encryption algorithms
...tions
They provide a mapping between an arbitrary length input, and a (usually) fixed length (or smaller length) output. It can be anything from a simple crc32, to a full blown cryptographic hash function such as MD5 or SHA1/2/256/512. The point is that there's a one-way mapping going on. It's a...