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Performance of Arrays vs. Lists
...the getter of the indexer of the List class, looks like this:
public T get_Item(int index)
{
if (index >= this._size)
{
ThrowHelper.ThrowArgumentOutOfRangeException();
}
return this._items[index];
}
As you can see, when you use the indexer of the List, the List performs...
On delete cascade with doctrine2
...de to the foreign key column in the database:
@ORM\JoinColumn(name="father_id", referencedColumnName="id", onDelete="CASCADE")
I also want to point out that the way you have your cascade={"remove"} right now, if you delete a Child object, this cascade will remove the Parent object. Clearly not wh...
In pure functional languages, is there an algorithm to get the inverse function?
...he functional languages have that option. For example:
f :: a -> Int
f _ = 1
This function does not have an inverse.
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PostgreSQL Crosstab Query
...m is also limited to exactly three columns in the provided input query: row_name, category, value. There is no room for extra columns like in the 2-parameter alternative below.
Safe form
crosstab(text, text) with 2 input parameters:
SELECT *
FROM crosstab(
'SELECT section, status, ct
FR...
What does 'require: false' in Gemfile mean?
...just set :require => false and then in your code have a require 'library_name_here'
– Rob Di Marco
Jan 5 '14 at 13:38
...
Use different Python version with virtualenv
...ses, languages and compilers galore! Thanks!
– zachd1_618
Jan 24 '13 at 18:03
4
Under virtualenv ...
How does inheritance work for Attributes?
...AttributeUsage (Inherited = True)]
MyUberAttribute : Attribute
{
string _SpecialName;
public string SpecialName
{
get { return _SpecialName; }
set { _SpecialName = value; }
}
}
Then use the Attribute by decorating a super-class...
[MyUberAttribute(SpecialName = "Bob")]
clas...
Block Comments in Clojure
... A word of warning -- the (comment) macro expands to nil. Use #_ to comment a single form, or #_(comment ...) to comment multiple forms without inserting a nil.
– treat your mods well
Dec 18 '11 at 2:55
...
What do ellipsis […] mean in a list?
... For me, instead of "..." it shows "<Recursion on dict with id=___>"
– Solomon Ucko
Apr 17 '16 at 23:30
...
What's the difference between size_t and int in C++?
In several C++ examples I see a use of the type size_t where I would have used a simple int . What's the difference, and why size_t should be better?
...