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Test if a variable is a list or tuple
...
How about: hasattr(a, "__iter__") ?
It tells if the object returned can be iterated over as a generator. By default, tuples and lists can, but not the string types.
share...
Update multiple rows in same query using PostgreSQL
... one column, it's much more generalizable:
update test as t set
column_a = c.column_a
from (values
('123', 1),
('345', 2)
) as c(column_b, column_a)
where c.column_b = t.column_b;
You can add as many columns as you like:
update test as t set
column_a = c.column_a,
column_c...
_DEBUG vs NDEBUG
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Visual Studio defines _DEBUG when you specify the /MTd or /MDd option, NDEBUG disables standard-C assertions. Use them when appropriate, ie _DEBUG if you want your debugging code to be consistent with the MS CRT debugging techniques and NDEBUG if ...
The most accurate way to check JS object's type?
... constructor:
Native Type Ex1:
var string1 = "Test";
console.log(string1.__proto__.constructor.name);
displays:
String
Ex2:
var array1 = [];
console.log(array1.__proto__.constructor.name);
displays:
Array
Custom Classes:
function CustomClass(){
console.log("Custom Class Object C...
Inserting multiple rows in mysql
...sed within parentheses and separated by commas.
Example:
INSERT INTO tbl_name
(a,b,c)
VALUES
(1,2,3),
(4,5,6),
(7,8,9);
Source
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How to implement a rule engine?
...;
// use a method call, e.g. 'Contains' -> 'u.Tags.Contains(some_tag)'
return Expression.Call(left, method, right);
}
}
Note that I used 'GreaterThan' instead of 'greater_than' etc. - this is because 'GreaterThan' is the .NET name for the operator, therefore we don't need any...
Rails I18n validation deprecation warning
... the following line inside the Rails::Application body
config.i18n.enforce_available_locales = true
The possible values are:
false: if you
want to skip the locale validation
don't care about locales
true: if you
want the application to raise an error if an invalid locale is passed (or)
wan...
Adding Core Data to existing iPhone project
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All the CoreData header files are imported in App_Prefix.pch, so the CoreData classes will be available throughout your Project, so you don't have to manually import the header in the files you need them.
So open up Xcode and look for some file like App_Prefix.pch, by defa...
pydot and graphviz error: Couldn't import dot_parser, loading of dot files will not be possible
...workX (e.g. this NetworkX example failed). I kept getting: global name 'dot_parser' is not defined. Your solution solved this problem.
– qtips
Aug 6 '13 at 0:41
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MongoDB atomic “findOrCreate”: findOne, insert if nonexistent, but do not update
as the title says, I want to perform a find (one) for a document, by _id, and if doesn't exist, have it created, then whether it was found or was created, have it returned in the callback.
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