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How to validate an email address using a regular expression?
...he IP address pattern that is floating around the internet with a bug that allows 00 for any of the unsigned byte decimal values in a dot-delimited address, which is illegal. The rest of it appears to be consistent with the RFC 5322 grammar and passes several tests using grep -Po, including cases d...
Difference between char* and const char*?
...dangerous, since you could do a segmetation fault memory, and if you are really smart you could hack the computer. That is why compilers always shown warnings in those implementations I think
– Daniel N.
May 15 '15 at 4:22
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iOS: How to store username/password within an app?
...ta and kSecAttrAccount in Objective-C code, so be sure to cast them using (__bridge id), e.g., [keychainItem setObject:obj forKey:(__bridge id)kSecValueData];
– Joe Hankin
Apr 6 '13 at 23:13
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How to tell if JRE or JDK is installed
I have one computer that I intentionally installed JDK on. I have another computer with JRE, for, among other things, testing. However, when I got a java application working on this computer, and then tried it on another, it complained that JDK was required. How can I check if JDK was somehow instal...
Python - 'ascii' codec can't decode byte
I'm really confused. I tried to encode but the error said can't decode... .
7 Answers
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Where do I find the current C or C++ standard documents?
...9:1990 Hardcopy available from SAI Global ($88 + shipping)
You cannot usually get old revisions of a standard (any standard) directly from the standards bodies shortly after a new edition of the standard is released. Thus, standards for C89, C90, C99, C++98, C++03 will be hard to find for purchas...
Why shouldn't I use PyPy over CPython if PyPy is 6.3 times faster?
...to mention, has tenuous support for C extensions. It has support, but typically at slower-than-Python speeds and it's iffy at best. Hence a lot of modules simply require CPython. PyPy doesn't support numpy PyPy now supports numpy. Some extensions are still not supported (Pandas, SciPy, etc.), take a...
Java how to replace 2 or more spaces with single space in string and delete leading and trailing spa
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Try this:
String after = before.trim().replaceAll(" +", " ");
See also
String.trim()
Returns a copy of the string, with leading and trailing whitespace omitted.
regular-expressions.info/Repetition
No trim() regex
It's also possible to do this with just one re...
Displaying the build date
...ing(0,16);}} > "$(ProjectDir)\BuildTimestamp.cs" - - - --> then can call it with Build.Timestamp
– FabianSilva
Jun 2 '14 at 16:10
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std::unique_lock or std::lock_guard?
...er you need to relock the guard.
std::unique_lock has other features that allow it to e.g.: be constructed without locking the mutex immediately but to build the RAII wrapper (see here).
std::lock_guard also provides a convenient RAII wrapper, but cannot lock multiple mutexes safely. It can be us...