大约有 49,000 项符合查询结果(耗时:0.0651秒) [XML]
How do I automatically update a timestamp in PostgreSQL
...the time of the actual current moment, (2) the time the statement started, and (3) the time the transaction started. The example shown here is start of current transaction. You may or may not want that as opposed to the other two possibilities.
– Basil Bourque
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How to check if a URL is valid
...by:
require 'uri'
if url =~ URI::regexp
# Correct URL
end
Like Alexander Günther said in the comments, it checks if a string contains a URL.
To check if the string is a URL, use:
url =~ /\A#{URI::regexp}\z/
If you only want to check for web URLs (http or https), use this:
url =~ /\A#{U...
Testing if object is of generic type in C#
...of inheritance. If, along the way, you have a base with both a base class and the interface you're looking for, this goes down the class path only.
– Groxx
Mar 18 '11 at 23:41
1
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How do I pass the value (not the reference) of a JS variable to a function? [duplicate]
...ange_selection(i);
});
})(i);
}
By creating an anonymous function and calling it with the variable as the first argument, you're passing-by-value to the function and creating a closure.
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Python idiom to return first item or None
...last option is almost exactly what I'm looking for: it's clear, it works, and it doesn't require me to define a new function. I'd say "exactly" if the break were somehow not needed, because the risk of omitting it is not insignificant. But this approach has the ring of truth.
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Node.js client for a socket.io server
I have a socket.io server running and a matching webpage with a socket.io.js client. All works fine.
5 Answers
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Git: Discard all changes on a diverged local branch
...branch blows away the branch's reflog. Resetting the branch, on the other hand not only preserves the reflog, but actually records the reset in the reflog. This makes the operation easily reversible later, if needed.
– Dan Moulding
Mar 30 '11 at 22:36
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Facebook Post Link Image
...posts a link on facebook, a script usually scans that link for any images, and displays a quick thumbnail next to the post. For certain URLs though (including mine), FB doesn't seem to pick up anything, despite their being a number of images on that page.
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Creating functions in a loop
... f(i=i): like this:
def f(i=i):
return i
Default values (the right-hand i in i=i is a default value for argument name i, which is the left-hand i in i=i) are looked up at def time, not at call time, so essentially they're a way to specifically looking for early binding.
If you're worried abo...
How to find out where a function is defined?
How can I find out in which file and line a given function was defined?
8 Answers
8
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