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How do I test for an empty JavaScript object?
... keys).
Pre-ECMA 5:
function isEmpty(obj) {
for(var prop in obj) {
if(obj.hasOwnProperty(prop)) {
return false;
}
}
return JSON.stringify(obj) === JSON.stringify({});
}
jQuery:
jQuery.isEmptyObject({}); // true
lodash:
_.isEmpty({}); // true
Underscore:
_.isEmpty({});...
Django migration strategy for renaming a model and relationship fields
...nameField('YetAnotherModel', 'foo', 'bar')
]
You may get some errors if you don't update the names where it's imported e.g. admin.py and even older migration files (!).
Update: As ceasaro mentions, newer versions of Django are usually able to detect and ask if a model is renamed. So try manag...
Get operating system info
... show which operating system someone is using.
What it does is that, it sniffs your core operating system model, for example windows nt 5.1 as my own.
It then passes windows nt 5.1/i to Windows XP as the operating system.
Using: '/windows nt 5.1/i' => 'Windows XP', from an array.
You could s...
Received an invalid column length from the bcp client for colid 6
... cell data that exceed the datacolumn datatype length in the database.
Verify the data in excel. Also verify the data in the excel for its format to be in compliance with the database table schema.
To avoid this, try exceeding the data-length of the string datatype in the database table.
Hope thi...
Does java.util.List.isEmpty() check if the list itself is null? [duplicate]
Does java.util.List.isEmpty() check if the list itself is null , or do I have to do this check myself?
8 Answers
...
Entity Framework .Remove() vs. .DeleteObject()
...ntity as Deleted in the context. (It's EntityState is Deleted after that.) If you call SaveChanges afterwards EF sends a SQL DELETE statement to the database. If no referential constraints in the database are violated the entity will be deleted, otherwise an exception is thrown.
EntityCollection.Rem...
Is short-circuiting logical operators mandated? And evaluation order?
... recommended to overload these operators in C++ unless you have a very specific requirement. You can do it, but it may break expected behaviour in other people's code, especially if these operators are used indirectly via instantiating templates with the type overloading these operators.
...
How to cancel a local git commit
...
@feresr If you really did not touch those files in the last commit or in the working tree this is caused by other inconsistencies in your working tree, e.g. you're on Windows and file endings do not match.
– Kor...
How do I remove repeated elements from ArrayList?
...
If you don't want duplicates in a Collection, you should consider why you're using a Collection that allows duplicates. The easiest way to remove repeated elements is to add the contents to a Set (which will not allow duplica...
Type.GetType(“namespace.a.b.ClassName”) returns null
...
Type.GetType("namespace.qualified.TypeName") only works when the type is found in either mscorlib.dll or the currently executing assembly.
If neither of those things are true, you'll need an assembly-qualified name:
Type.GetType("namespace.qualified.T...