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What is an “unwrapped value” in Swift?
...st, you have to understand what an Optional type is. An optional type basically means that the variable can be nil.
Example:
var canBeNil : Int? = 4
canBeNil = nil
The question mark indicates the fact that canBeNil can be nil.
This would not work:
var cantBeNil : Int = 4
cantBeNil = nil // can...
Convert UTC to local time in Rails 3
...mes. See them with:
rake time:zones:us
You can also run rake time:zones:all for all time zones.
To see more zone-related rake tasks: rake -D time
So, to convert to EST, catering for DST automatically:
Time.now.in_time_zone("Eastern Time (US & Canada)")
...
Are the days of passing const std::string & as a parameter over?
...he said is because of cases like this.
Let's say I have function A which calls function B, which calls function C. And A passes a string through B and into C. A does not know or care about C; all A knows about is B. That is, C is an implementation detail of B.
Let's say that A is defined as follow...
How to install packages using pip according to the requirements.txt file from a local directory?
...
This works for me:
$ pip install -r requirements.txt --no-index --find-links file:///tmp/packages
--no-index - Ignore package index (only looking at --find-links URLs instead).
-f, --find-links <URL> - If a URL or path to an html file, then par...
C/C++ Struct vs Class
After finishing my C++ class it seemed to me the structs/classes are virtually identical except with a few minor differences.
...
What is the correct XPath for choosing attributes that contain “foo”?
Given this XML, what XPath returns all elements whose prop attribute contains Foo (the first three nodes):
9 Answers
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Java Synchronized Block for .class
What does this java code mean? Will it gain lock on all objects of MyClass ?
4 Answers
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Should enums in C# have their own file? [closed]
..." (how much does an extra file cost?), but it is often inconventient. Usually there's one class that's most closely associtated with the enum, and I put them in the same file.
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How to suppress Pandas Future warning ?
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@bdiamante's answer may only partially help you. If you still get a message after you've suppressed warnings, it's because the pandas library itself is printing the message. There's not much you can do about it unless you edit the Pandas source code yoursel...
resizes wrong; appears to have unremovable `min-width: min-content`
...scribed below is fixed as of Firefox 53 and the link to this answer has finally been removed from Bootstrap's documentation.
Also, my sincere apologies to the Mozilla contributors who had to block removing support for -moz-document partly due to this answer.
The fix
In WebKit and Firefox 53+, you...