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To ARC or not to ARC? What are the pros and cons? [closed]
...ge collection. It has no GC runtime overhead. The compiler inserts retains and releases in all the places you should have anyway. But it's smarter than you and can optimize out the ones that aren't actually needed (just like it can unroll loops, eliminate temporary variables, inline functions, etc.)...
How to Join to first row
...
WHERE OrderID = Orders.OrderID
)
In SQL Server 2005 and above, you could just replace INNER JOIN with CROSS APPLY:
SELECT Orders.OrderNumber, LineItems2.Quantity, LineItems2.Description
FROM Orders
CROSS APPLY
(
SELECT TOP 1 LineItems.Quantity, LineItems....
Is string in array?
...e new readers to know that there is a new method to do this using generics and extension methods.
You can read my blog post to see more information about how to do this, but the main idea is this:
By adding this extension method to your code:
public static bool IsIn<T>(this T source, params...
How do I access properties of a javascript object if I don't know the names?
...ke this:
for (var key in data) {
console.log(key);
}
This logs "Name" and "Value".
If you have a more complex object type (not just a plain hash-like object, as in the original question), you'll want to only loop through keys that belong to the object itself, as opposed to keys on the object's...
Calculate difference in keys contained in two Python dictionaries
Suppose I have two Python dictionaries - dictA and dictB . I need to find out if there are any keys which are present in dictB but not in dictA . What is the fastest way to go about it?
...
How to set date format in HTML date input tag?
... displays in is (generally speaking) the correct one for the user's locale and the format that the user is used to writing/understanding dates in.
If you mean the format in which it's transmitted to the server, you're trying to fix the wrong problem. What you need to do is program the server-side ...
How do I get the first element from an IEnumerable in .net?
...often want to grab the first element of an IEnumerable<T> in .net, and I haven't found a nice way to do it. The best I've come up with is:
...
Clone Object without reference javascript [duplicate]
I have a big object with much data. And i want to clone this in other variable. When i set some param of the instance B has the same result in the original object:
...
Select the values of one property on all objects of an array in PowerShell
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I think you might be able to use the ExpandProperty parameter of Select-Object.
For example, to get the list of the current directory and just have the Name property displayed, one would do the following:
ls | select -Property Name
This is still returning Direc...
What's the difference between String(value) vs value.toString()
Javascript has lot's of "tricks" around types and type conversions so I'm wondering if these 2 methods are the same or if there is some corner case that makes them different?
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