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NSLog the method name with Objective-C in iPhone
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print(__FUNCTION__) // Swift
NSLog(@"%@", NSStringFromSelector(_cmd)); // Objective-C
Swift 3 and above
print(#function)
share
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Ruby send vs __send__
I understand the concept of some_instance.send but I'm trying to figure out why you can call this both ways. The Ruby Koans imply that there is some reason beyond providing lots of different ways to do the same thing. Here are the two examples of usage:
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Selecting multiple columns in a pandas dataframe
...).
df1 = df[['a', 'b']]
Alternatively, if it matters to index them numerically and not by their name (say your code should automatically do this without knowing the names of the first two columns) then you can do this instead:
df1 = df.iloc[:, 0:2] # Remember that Python does not slice inclusive of...
How do you trigger a block after a delay, like -performSelector:withObject:afterDelay:?
Is there a way to call a block with a primitive parameter after a delay, like using performSelector:withObject:afterDelay: but with an argument like int / double / float ?
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Select distinct values from a table field
...ant any ordering to be applied to a query, not even the default ordering, call order_by() with no parameters.
and distinct() in the note where it discusses issues with using distinct() with ordering.
To query your DB, you just have to call:
models.Shop.objects.order_by().values('city').distinct(...
How to validate an Email in PHP?
...hould be replaced by the preg family (PCRE Regex Functions). There are a small amount of differences, reading the Manual should suffice.
Update 1: As pointed out by @binaryLV:
PHP 5.3.3 and 5.2.14 had a bug related to
FILTER_VALIDATE_EMAIL, which resulted in segfault when validating
large ...
Vagrant error : Failed to mount folders in Linux guest
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The plugin vagrant-vbguest solved my problem:
$ vagrant plugin install vagrant-vbguest
Output:
$ vagrant reload
==> default: Attempting graceful shutdown of VM...
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==> default: Machine booted and ready!
GuestAdditions 4.3.12 running --- OK.
==> default: Checking for guest addi...
How do I override __getattr__ in Python without breaking the default behavior?
I want to override the __getattr__ method on a class to do something fancy but I don't want to break the default behavior.
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Ruby on Rails: Delete multiple hash keys
...re unaware of the Hash#except method ActiveSupport adds to Hash.
It would allow your code to be simplified to:
redirect_to my_path(params.except(:controller, :action, :other_key))
Also, you wouldn't have to monkey patch, since the Rails team did it for you!
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How to change the Eclipse default workspace?
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It doesnt allow me to move this folder anywhere outside of my working folder...Is there any workarounds to move this folder into another drive?
– Laserson
Mar 17 '13 at 14:43
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