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Where are static variables stored in C and C++?
...program execution passes through its
definition. The order of initialization of
global variables across translation units is not
defined, and special care is needed to manage
dependencies between global objects (inc...
Primary key or Unique index?
...value appears nowhere, if the value is used for nothing? It's make-work in order to stop Access from asking for a PK. Make a PK if you need to identify the record in a child, otherwise it's a waste.
– Mark Brady
Feb 16 '09 at 20:57
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Do I set properties to nil in dealloc when using ARC?
... must behave correctly if you pass it a nil value) and sometimes watch the order of deallocation.
– Sulthan
Mar 7 '12 at 21:23
7
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How can I get nth element from a list?
...6
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`- 7
We can now access the elements of the tree in depth-first order:
> tree ^? element 0
Just 1
> tree ^? element 1
Just 2
> tree ^? element 2
Just 4
> tree ^? element 3
Just 5
> tree ^? element 4
Just 3
> tree ^? element 5
Just 6
> tree ^? element 6
Just 7
We ca...
Accessing class variables from a list comprehension in the class definition
...[i for i in range(1) for j in range(x)]
This design decision was made in order to throw an error at genexp creation time instead of iteration time when creating the outermost iterable of a generator expression throws an error, or when the outermost iterable turns out not to be iterable. Comprehens...
Strings as Primary Keys in SQL Database [closed]
... a primary key is that because the index is constantly put into sequential order, when a new key is created that would be in the middle of the order the index has to be resequenced... if you use an auto number integer, the new key is just added to the end of the index.
...
How does type Dynamic work and how to use it?
... If you use do checks at runtime, you have to do the parameter checking in order to dispatch correctly to the right code path. That shouldn't be more overhead than any other parameter checking in your application has. If you make use of reflection, you get obviously more overhead but you have to mea...
Make column not nullable in a Laravel migration
...e doctrine/dbal
Then create a migration that will alter the table like so:
php artisan make:migration fix_whatever_table_name_here
public function up()
{
Schema::table('table_name', function (Blueprint $table) {
$table->type('column')->nullable(false)->change();
});
}
# pub...
How to detect if a script is being sourced
...ipt or on the line after the shebang (which, if used, should be for ksh in order for it to work under the most circumstances).
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Selecting multiple columns in a pandas dataframe
...mns, like df.ix[0, 'Col1':'Col5']. That gets all columns that happen to be ordered between Col1 and Col5 in the df.columns array. It is incorrect to say that ix indexes rows. That is just its most basic use. It also supports much more indexing than that. So, ix is perfectly general for this question...