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How do the likely/unlikely macros in the Linux kernel work and what is their benefit?
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They are hint to the compiler to emit instructions that will cause branch prediction to favour the "likely" side of a jump instruction. This can be a big win, if the prediction is correct it means that the jump instruction is basically free and will take zero ...
Format timedelta to string
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You can just convert the timedelta to a string with str(). Here's an example:
import datetime
start = datetime.datetime(2009,2,10,14,00)
end = datetime.datetime(2009,2,10,16,00)
delta = end-start
print(str(delta))
# prints 2:00:00
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Perform .join on value in array of objects
... array of strings, I can use the .join() method to get a single string, with each element separated by commas, like so:
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What is the difference between visibility:hidden and display:none?
The CSS rules visibility:hidden and display:none both result in the element not being visible. Are these synonyms?
18 A...
The 'json' native gem requires installed build tools
...running them and before the last attempt to install the gem that wants devkit present?
Also, be sure you are using the right devkit installer for your version of Ruby. The documentation at devkit wiki page has a requirements note saying:
For RubyInstaller versions 1.8.7, 1.9.2, and 1.9.3 use ...
How do I cast a string to integer and have 0 in case of error in the cast with PostgreSQL?
In PostgreSQL I have a table with a varchar column. The data is supposed to be integers and I need it in integer type in a query. Some values are empty strings.
The following:
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How can I search Git branches for a file or directory?
In Git, how could I search for a file or directory by path across a number of branches?
6 Answers
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The type or namespace name 'DbContext' could not be found [closed]
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I had the same issue. Turns out, you need the EntityFramework.dll reference (and not System.Data.Entity).
I just pulled it from the MvcMusicStore application which you can download from: http://mvcmusicstore.codeplex.com/
It's also a useful example of how to use entity fr...
What data type to use for hashed password field and what length?
I'm not sure how password hashing works (will be implementing it later), but need to create database schema now.
10 Answers...
How to create a Menubar application for Mac
EDIT: This is a nice ready-made menubar application here ( github source ) by this answer .
6 Answers
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