大约有 48,000 项符合查询结果（耗时：0.0677秒） [XML]
What is a regular expression for a MAC Address?
...
The standard (IEEE 802) format for
printing MAC-48 addresses in
human-friendly form is six groups of
two hexadecimal digits, separated by
hyphens - or colons :.
So:
^([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})$
...
Why is reading lines from stdin much slower in C++ than Python?
I wanted to compare reading lines of string input from stdin using Python and C++ and was shocked to see my C++ code run an order of magnitude slower than the equivalent Python code. Since my C++ is rusty and I'm not yet an expert Pythonista, please tell me if I'm doing something wrong or if I'm mis...
Landscape printing from HTML
I have a HTML report, which needs to be printed landscape because of the many columns. It there a way to do this, without the user having to change the document settings?
...
What are the details of “Objective-C Literals” mentioned in the Xcode 4.4 release notes?
I was going through the release notes for Xcode 4.4 and noticed this:
3 Answers
3
...
How to merge dictionaries of dictionaries?
...for key in b:
if key in a:
if isinstance(a[key], dict) and isinstance(b[key], dict):
merge(a[key], b[key], path + [str(key)])
elif a[key] == b[key]:
pass # same leaf value
else:
raise Exception('Conflict at %...
How to use multiple arguments for awk with a shebang (i.e. #!)?
...sr/bin/gawk" "--re-interval" "-f" "$0" "$@", but awk treated that as a command and printed out every line of input unconditionally. That is why I put in the arbitrary_long_name==0 - it's supposed to fail all the time. You could replace it with some gibberish string. Basically, I was looking for a fa...
Learning Regular Expressions [closed]
I don't really understand regular expressions. Can you explain them to me in an easy-to-follow manner? If there are any online tools or books, could you also link to them?
...
What's the difference between ViewData and ViewBag?
...
It uses the C# 4.0 dynamic feature. It achieves the same goal as viewdata and should be avoided in favor of using strongly typed view models (the same way as viewdata should be avoided).
So basically it replaces magic strings:
ViewData["Foo"]
with magic properties:
ViewBag.Foo
for which you ...
How to do a LIKE query in Arel and Rails?
...(users[:name].matches("%#{params[:user_name]}%")), I tried TRUNCATE users; and other such queries and nothing happened on the sql side. Looks safe to me.
– earlonrails
Aug 28 '13 at 18:56
...
Retrieve specific commit from a remote Git repository
... on my PC? The structure of remote repo is absolutely same as that of mine and hence there won't be any conflicts but I have no idea how to do this and I don't want to clone that huge repository.
...