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ActiveRecord, has_many :through, and Polymorphic Associations
...rying to define.
This fix to the Widget model should allow you do exactly what you're looking for.
class Widget < ActiveRecord::Base
has_many :widget_groupings
has_many :people, :through => :widget_groupings, :source => :grouper, :source_type => 'Person'
has_many :aliens, :throu...
Selecting data frame rows based on partial string match in a column
...es(mtcars) %like% "Merc", ]
iris[iris$Species %like% "osa", ]
If that is what you had, then perhaps you had just mixed up row and column positions for subsetting data.
If you don't want to load a package, you can try using grep() to search for the string you're matching. Here's an example with ...
Can the :not() pseudo-class have multiple arguments?
...
What? so you would rather write .selector:not(.one):not(.two):not(.three):not(.four) { ... } than .selector { @include not('.one','.two','.three','.four') { ... } } ?
– Daniel Tonon
Jun ...
Cast an instance of a class to a @protocol in Objective-C
...ight or might not care about the object type, it depends on the situation. What happens if you want to send a message declared on UIViewController to vc in the example in my answer, and it's declared as id <MyProtocol>?
– Nick Forge
Dec 1 '13 at 15:41
...
Escaping quotes and double quotes
...rver\toto.exe -batch=B -param="sort1;parmtxt='Security ID=1234'"
Is that what you were looking for?
The error PowerShell gave me referred to an unexpected token 'sort1', and that's how I determined where to put the backticks.
The @' ... '@ syntax is called a "here string" and will return exactly...
regex for matching something if it is not preceded by something else
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what modifications need to be made to not match foo_arbitrary_bar? ie foo not immediately preceding bar
– Brad Kent
Jun 28 '18 at 1:43
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Regex Named Groups in Java
...med group, unless you code your own version of Regex...
That is precisely what Gorbush2 did in this thread.
Regex2
(limited implementation, as pointed out again by tchrist, as it looks only for ASCII identifiers. tchrist details the limitation as:
only being able to have one named group per s...
SQL Server: Database stuck in “Restoring” state
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I've never had to use the recovery statement when doing what he is doing. WITH REPLACE should suffice.
– Sam
Feb 6 '09 at 20:23
8
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Inheriting class methods from modules / mixins in Ruby
... needed to understand why module inclusion works the way it does in Ruby.
What happens when a module is included?
Including a module into a class adds the module to the ancestors of the class. You can look at the ancestors of any class or module by calling its ancestors method:
module M
def foo...
PHP - Modify current object in foreach loop
...r[$i] = is_int($item) ? $item * 2 : $item;
}
var_dump($arr);
If you know what you are doing will never have mutability problems (bearing in mind if you intend upon overwriting $arr you could always $arr = array_map and be explicit.
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