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What is the proper way to check if a string is empty in Perl?
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For string comparisons in Perl, use eq or ne:
if ($str eq "")
{
// ...
}
The == and != operators are numeric comparison operators. They will attempt to convert both operands to integers before comparing them.
See the perlop man pa...
How to get the number of Characters in a String?
...", len("世界"), utf8.RuneCountInString("世界"))
}
Phrozen adds in the comments:
Actually you can do len() over runes by just type casting.
len([]rune("世界")) will print 2. At leats in Go 1.3.
And with CL 108985 (May 2018, for Go 1.11), len([]rune(string)) is now optimized. (Fixes issue 2492...
What is the difference between GitHub and gist?
... However, everything is driven by git revision control, so gists also have complete revision histories.
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Difference between shared objects (.so), static libraries (.a), and DLL's (.so)?
...correct. The header file defines prototypes which are required in order to compile the code which uses the library, but at link time the linker looks inside the library itself to make sure the functions it needs are actually there. The linker has to find the function bodies somewhere at link time or...
return query based on date
... equals), because this is often used for date-only queries, where the time component is 00:00:00.
If you really want to find a date that equals another date, the syntax would be
db.gpsdatas.find({"createdAt" : new ISODate("2012-01-12T20:15:31Z") });
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Can't specify the 'async' modifier on the 'Main' method of a console app
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As you discovered, in VS11 the compiler will disallow an async Main method. This was allowed (but never recommended) in VS2010 with the Async CTP.
I have recent blog posts about async/await and asynchronous console programs in particular. Here's some backg...
How to check whether a file or directory exists?
...ver. Explicitly returning an err as a second return value is an extremely common, idiomatic Go technique. See: golang.org/doc/effective_go.html#errors
– Chris Pfohl
Aug 13 '13 at 20:19
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Command to change the default home directory of a user
I would like to know whether there is any simple shell command to change the user home directory in Linux/Unix (one similar to chsh which changes the default login shell of an existing valid user) without touching the /etc/passwd file. Thanks
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How do I make a checkbox required on an ASP.NET form?
...this is the right way to do this". To answer the most frequently occurring complaint against this question: "checkboxes can have two legitimate states - checked and unchecked", this is an "I accept the terms and conditions..." checkbox which must be checked in order to complete a registration, hence...