大约有 40,000 项符合查询结果（耗时：0.0545秒） [XML]
Extract a regular expression match
...([0-9]+).*", "\\1", "aaa12xx99",perl=TRUE)
[1] "12"
Trying to substitute out non-digits will lead to an error in this case.
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resizes wrong; appears to have unremovable `min-width: min-content`
...et element is absurd and essentially impossible to specify in CSS. Think about it: the fieldset's border disappears where it's overlapped by a legend element, but the background remains visible! There's no way to reproduce this with any other combination of elements.
To top it off, implementations ...
Are there any standard exit status codes in Linux?
...valid argument to exit
128+n: Fatal error signal "n"
255: Exit status out of range (exit takes only integer args in the range 0 - 255)
Part 2: sysexits.h
The ABSG references sysexits.h.
On Linux:
$ find /usr -name sysexits.h
/usr/include/sysexits.h
$ cat /usr/include/sysexits.h
/*
* Copy...
What does it mean when git says a file “needs update”?
...explanation of the "[file]: needs update" message that git sometimes spits out from time to time. Even the official git FAQ has explaining this marked as a TODO. If someone could explain A) what it means; and B) how to fix it, I would be extremely grateful.
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Python Requests and persistent sessions
...ing the requests module (version 0.10.0 with Python 2.5).
I have figured out how to submit data to a login form on a website and retrieve the session key, but I can't see an obvious way to use this session key in subsequent requests.
Can someone fill in the ellipsis in the code below or suggest an...
Why use 'git rm' to remove a file instead of 'rm'?
... Good answer. I was able to use git reset --hard and then do a checkout of master to get out of detached head state because I knew I didn't have any uncommitted changes. If you haven't committed your changes you may want to do a git stash, but I'm relatively new to git so I don't know the exa...
Single Sign On across multiple domains [closed]
...eates a cookie storing the session id from the master. The client can find out the logged in user by querying the shared database using the session id.
Notes:
The session id is a unique global identifier generated with algorithm from RFC 4122
The master_login.php will only redirect to domains in...
How can I check for “undefined” in JavaScript? [duplicate]
...
If you are interested in finding out whether a variable has been declared regardless of its value, then using the in operator is the safest way to go. Consider this example:
// global scope
var theFu; // theFu has been declared, but its value is undefined
t...
How to get the seconds since epoch from the time + date output of gmtime()?
...0:02:58 UTC', '%b %d, %Y @ %H:%M:%S UTC'))
1247169778
More information about calendar module here
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Fastest method of screen capturing on Windows
...are of is to use GDI, but I'm curious whether there are other ways to go about this, and, if there are, which incurs the least overhead? Speed is a priority.
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