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How can I return NULL from a generic method in C#?
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Two options:
Return default(T) which means you'll return null if T is a reference type (or a nullable value type), 0 for int, '\0' for char, etc. (Default values table (C# Reference))
Restrict T to be a reference type with the where T : class constraint and then return null as normal
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How to send an email with Python?
... following example (reproduced from the Python documentation). Notice that if you follow this approach, the "simple" task is indeed simple, and the more complex tasks (like attaching binary objects or sending plain/HTML multipart messages) are accomplished very rapidly.
# Import smtplib for the act...
How exactly does a generator comprehension work?
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Do you understand list comprehensions? If so, a generator expression is like a list comprehension, but instead of finding all the items you're interested and packing them into list, it waits, and yields each item out of the expression, one by one.
>>> my...
I just discovered why all ASP.Net websites are slow, and I am trying to work out what to do about it
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If your page does not modify any session variables, you can opt out of most of this lock.
<% @Page EnableSessionState="ReadOnly" %>
If your page does not read any session variables, you can opt out of this lock entir...
Determining the last changelist synced to in Perforce
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p4 changes -m1 @clientname
they note a few gotchas:
This only works if you have not submitted anything from the workspace in question.
It is also possible that a client workspace is not synced to any specific changelist.
and there's an additional gotcha they don't mention:
If the highes...
uint8_t vs unsigned char
...ll be storing small numbers, rather than a character.
Also it looks nicer if you're using other typedefs such as uint16_t or int32_t.
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Java array reflection: isArray vs. instanceof
Is there a preference or behavior difference between using:
8 Answers
8
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Should one use < or
If you had to iterate through a loop 7 times, would you use:
39 Answers
39
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Add primary key to existing table
...ption in the case of composite PKs for performance on insertion date basis if that is important for you.
– Shiv
Feb 10 '17 at 5:23
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Get position of UIView in respect to its superview's superview
...ect frame = [firstView convertRect:buttons.frame fromView:secondView];
Swift
let frame = firstView.convert(buttons.frame, from:secondView)
Documentation reference:
https://developer.apple.com/documentation/uikit/uiview/1622498-convert
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