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C# nullable string error
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System.String is a reference type and already "nullable".
Nullable<T> and the ? suffix are for value types such as Int32, Double, DateTime, etc.
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SQLite select where empty?
...n I select records where some_column is empty?
Empty counts as both NULL and "".
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In Jinja2, how do you test if a variable is undefined?
Converting from Django, I'm used to doing something like this:
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Combine multiple Collections into a single logical Collection?
...terate over all elements (ideally, read only).
I'm using guava collections and I wonder how I could use guava iterables/iterators to generate a logical view on the internal collections without making temporary copies.
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How to find the length of a string in R
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nchar(YOURSTRING)
you may need to convert to a character vector first;
nchar(as.character(YOURSTRING))
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Terminating a script in PowerShell
... via CLI e.g. powershell -command "& module-function ...". I needed to convert those functions to throw to a wrapping try-catch and exit from that wrapping catch in order to actually output an error exit code.
– Josh
Mar 16 '16 at 14:37
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Using Emacs as an IDE
...tangle functions can be really useful for taking a dump from some tool and converting it to useful data such as an elisp program or a comma delimited spreadsheet.
I wrote a page about IDE like things you can do with emacs
http://justinsboringpage.blogspot.com/2007/09/11-visual-studio-tricks-in-e...
String is immutable. What exactly is the meaning? [duplicate]
...ith the fuss of immutability, let's just take a look into the String class and its functionality a little before coming to any conclusion.
This is how String works:
String str = "knowledge";
This, as usual, creates a string containing "knowledge" and assigns it a reference str. Simple enough? Le...
Why can tuples contain mutable items?
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One reason is that there is no general way in Python to convert a mutable type into an immutable one (see the rejected PEP 351, and the linked discussion for why it was rejected). Thus, it would be impossible to put various types of objects in tuples if it had this restriction, in...
How do I read configuration settings from Symfony2 config.yml?
... the first approach and the documentation, it's that the config values are converted into parameters in the MyNiceProjectExtension->load() method with this line: $container->setParameter( 'my_nice_project.contact_email', $processedConfig[ 'contact_email' ]);. Thanks Xavi!
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