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Why isn't ProjectName-Prefix.pch created automatically in Xcode 6?
...ting macros unless there is no other way (such as when you need __FILE__). If you do need macros, put them in a header and include it.
The prefix header was necessary for things that are huge and used by nearly everything in the whole system (like Foundation.h). If you have something that huge and ...
What is a semaphore?
...ere are a dedicated number of people that are allowed in the club at once. If the club is full no one is allowed to enter, but as soon as one person leaves another person might enter.
It's simply a way to limit the number of consumers for a specific resource. For example, to limit the number of sim...
What's the equivalent of Java's Thread.sleep() in Objective-C/Cocoa?
... done on a join operation on a JAVA thread. You sleep for 10 millis, check if the thread is dead then you can dealloc it.
– Mike S
Sep 20 '10 at 6:45
1
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Rails: where does the infamous “current_user” come from?
...his only come from Devise? and do I have to manually define it myself even if I use Devise? Are there prerequisites to using current_user (like the existence of sessions, users, etc)?
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Is there a way to list open transactions on SQL Server 2000 database?
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Very useful, thank you! If it answered the OP's question (SQL 2000), it should have been the accepted answer. Have an upvote...
– Reversed Engineer
Sep 13 '18 at 9:06
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CURL alternative in Python
...ON decoding is handy as well. No need to manually load the body with json if the appropriate content-type is set.
– Thomas Farvour
Dec 17 '13 at 21:36
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@Html.BeginForm Displaying “System.Web.Mvc.Html.MvcForm” on Page
I have a razor view that I added a delete button to inside of an 'if' statement and when the view is rendered in the browser it is displaying "System.Web.Mvc.Html.MvcForm" next to the delete button.
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Pragma in define macro
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If you're using c99 or c++0x there is the pragma operator, used as
_Pragma("argument")
which is equivalent to
#pragma argument
except it can be used in macros (see section 6.10.9 of the c99 standard, or 16.9 of the c++0...
Where should Rails 3 custom validators be stored?
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If you place your custom validators in app/validators they will be automatically loaded without needing to alter your config/application.rb file.
sha...
How to create a MySQL hierarchical recursive query
...cte
on p.parent_id = cte.id
)
select * from cte;
The value specified in parent_id = 19 should be set to the id of the parent you want to select all the descendants of.
MySQL 5.x
For MySQL versions that do not support Common Table Expressions (up to version 5.7), you would achieve this ...