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Combine two ActiveRecord::Relation objects
...lation.or(last_name_relation)
† Only in ActiveRecord 5+; for 4.2 install the where-or backport.
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Better way to check variable for null or empty string?
...solves it, I'm not sure if it's simpler. +1 anyway
– Allain Lalonde
Dec 19 '08 at 15:36
4
Since O...
UML class diagram enum
...ML screenshot.
– Petri Tuononen
May 10 '12 at 7:32
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iOS 7 - Status bar overlaps the view
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Xcode 5 has iOS 6/7 Deltas which is specifically made to resolve this issue. In the storyboard, I moved my views 20 pixels down to look right on iOS 7 and in order to make it iOS 6 compatible, I changed Delta y to -20.
Since my storyboard is not using auto-layout,...
iOS 7 parallax effect in my view controller
... to the orientation of the user’s device. For example, to emulate the parallax effect on the home screen, you can use the subclass UIInterpolationMotionEffect, as explained here and here, just with a few lines of code.
Objective-C:
// Set vertical effect
UIInterpolatingMotionEffect *verticalMoti...
Inherit docstrings in Python class inheritance
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answered Jan 8 '10 at 4:51
John FeminellaJohn Feminella
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Why would a JavaScript variable start with a dollar sign? [duplicate]
...wish the jquery documentation used this notation as well... It is indeed really helpful.
– pedromanoel
Jan 28 '14 at 11:05
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SQLAlchemy - Getting a list of tables
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All of the tables are collected in the tables attribute of the SQLAlchemy MetaData object. To get a list of the names of those tables:
>>> metadata.tables.keys()
['posts', 'comments', 'users']
If you're using the...
How do you round a floating point number in Perl?
.... For rounding to a certain number of digits, sprintf() or printf() is usually the easiest
route.
printf("%.3f", 3.1415926535); # prints 3.142
The POSIX module (part of the standard Perl distribution) implements
ceil(), floor(), and a number of other mathematical and trigonometric
func...
What is the meaning of “POSIX”?
... and I read it every time I encounter the term. The fact is that I never really understood what it is.
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