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When to make a type non-movable in C++11?
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Herb's answer (before it was edited) actually gave a good example of a type which shouldn't be movable: std::mutex.
The OS's native mutex type (e.g. pthread_mutex_t on POSIX platforms) might not be "location invariant" meaning the object's address is part of its va...
Why are C# 3.0 object initializer constructor parentheses optional?
It seems that the C# 3.0 object initializer syntax allows one to exclude the open/close pair of parentheses in the constructor when there is a parameterless constructor existing. Example:
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Split List into Sublists with LINQ
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GroupBy doesn't return anything until it's enumerated all elements. That's why it's slow. The lists OP wants are contiguous, so a better method could yield the first sublist [a,g,e] before enumerating any more of the original list.
– Colonel Panic
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When to add what indexes in a table in Rails
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Should I add "index" to all the foreign keys like "xxx_id"?
It would be better, because it accelerates the search in sorting in this column. And Foreign keys are something searched for a lot.
Since Version 5 of rails the index will be created aut...
Chaining multiple MapReduce jobs in Hadoop
... edited yesterday
Max Niebergall
3855 bronze badges
answered Mar 24 '10 at 22:31
Binary NerdBinary Nerd
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How to select the first element with a specific attribute using XPath
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This will get all books from 'US'. (/bookstore/book[@location='US'])[1] will get the first one.
– Kevin Driedger
Apr 17 '12 at 19:39
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How do I put double quotes in a string in vba?
... & sPath & vbDoubleQuote, vbNormalFocus
– gicalle
Sep 11 '14 at 9:34
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Check if a table exists in Rails
...? 'kittens'
In Rails 2, 3 & 4 the API is about tables.
# Listing of all tables and views
ActiveRecord::Base.connection.tables
# Checks for existence of kittens table/view (Kitten model)
ActiveRecord::Base.connection.table_exists? 'kittens'
Getting the status of migrations:
# Tells you all...
Master-master vs master-slave database architecture?
...t seems to offer everything, no single point of failure, everyone can work all the time. The trouble with this is that it is very hard to preserve absolute consistency. See the wikipedia article for more.
Wikipedia seems to have a nice summary of the advantages and disadvantages
Advantages
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Exclude .svn directories from grep [duplicate]
...n directories. Is it possible to recursively grep a directory, but exclude all results from .svn directories?
11 Answers
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