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Should I use 'has_key()' or 'in' on Python dicts?
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in is definitely more pythonic.
In fact has_key() was removed in Python 3.x.
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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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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...
Using unset vs. setting a variable to empty
...t; unset var
/home/user1> echo $var
-bash: var: unbound variable
So really, it depends on how you are going to test the variable.
I will add that my preferred way of testing if it is set is:
[[ -n $var ]] # True if the length of $var is non-zero
or
[[ -z $var ]] # True if zero length
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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...
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...
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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How do you disable the unused variable warnings coming out of gcc in 3rd party code I do not wish to
...ut the stuff you have no control over.
For example, instead of -IC:\\boost_1_52_0, say -isystem C:\\boost_1_52_0.
Hope it helps. Good Luck!
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How to drop a table if it exists?
...e an error if the table does not exist).
Instead, for a permanent table you can use
IF OBJECT_ID('dbo.Scores', 'U') IS NOT NULL
DROP TABLE dbo.Scores;
Or, for a temporary table you can use
IF OBJECT_ID('tempdb.dbo.#T', 'U') IS NOT NULL
DROP TABLE #T;
SQL Server 2016+ has a better way, ...
SQL Server database backup restore on lower version
...R2 or
restore the backup you have on a SQL Server 2008 R2 instance, export all the data and import it on a SQL Server 2008 database.
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