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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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In Jinja2, how do you test if a variable is undefined?
Converting from Django, I'm used to doing something like this:
6 Answers
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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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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...
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...
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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What is the native keyword in Java for?
... actual implementation doesn’t have to use JNI. Certain JRE methods are handled intrinsically by the JVM. In fact, it’s not even mandatory that the implementation is actually native code. It’s just “implemented in a language other than the Java programming language”.
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Sorting a Python list by two fields
...For example, the columns to be used as keys are all strings that cannot be converted to numbers. Secondly, one wants to sort in ascending order by one column and descending order by another column.
– coder.in.me
Sep 25 '16 at 9:00
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