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How can I convert a string to a number in Perl?
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You don't need to convert it at all:
% perl -e 'print "5.45" + 0.1;'
5.55
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Why should hash functions use a prime number modulus?
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Usually a simple hash function works by taking the "component parts" of the input (characters in the case of a string), and multiplying them by the powers of some constant, and adding them together in some integer type. So for e...
How do I determine file encoding in OS X?
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That's a function call you would use if you want to write a program. From the command line, just type ls -l@ <filename> to see what attributes are set for the file. To see the actual attribute, type xattr -p com.apple.TextEncoding <fil...
http to https apache redirection
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I have actually followed this example and it worked for me :)
NameVirtualHost *:80
<VirtualHost *:80>
ServerName mysite.example.com
Redirect permanent / https://mysite.example.com/
</VirtualHost>
<VirtualHost _de...
“From View Controller” disappears using UIViewControllerContextTransitioning
... goes black. The key UIWindow is completely empty – no view hierarchy at all!
I played around a bit and it looks like there is an easy workaround, for simple cases. You can just re-add the toViewController's view as a subview of the key window's:
transitionContext.completeTransition(true)
UIAp...
What's the simplest way to test whether a number is a power of 2 in C++?
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so basically (n>0 && ((n & (n-1)) == 0))
– Saurabh Goyal
Jul 10 '16 at 8:06
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What are the drawbacks of Stackless Python? [closed]
...and it seems to have many advantages compared with vanilla cPython. It has all those cool features like infinite recursion, microthreads, continuations, etc. and at the same time is faster than cPython (around 10%, if the Python wiki is to be believed) and compatible with it (at least versions 2...
How to get a subset of a javascript object's properties
...og(picked); // { a: 5, c: 7 }
From Philipp Kewisch:
This is really just an anonymous function being called instantly. All of this can be found on the Destructuring Assignment page on MDN. Here is an expanded form
let unwrap = ({a, c}) => ({a, c});
let unwrap2 = function({a, ...
Passing a dictionary to a function as keyword parameters
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This is great, just used it with argparse/__dict__ to make it really easy to do command line argument parsing directly into options for a class object.
– Horus
Jun 14 '12 at 3:47
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Rake just one migration
...n a single migration that changed and needed to be re-run independently of all other migrations. Fire up the console and do this:
>> require 'db/migrate/your_migrations.rb'
=> ["YourMigrations"]
>> YourMigrations.up
=> etc... as the migration runs
>> YourMigration.down
Mor...