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Scala: Nil vs List()
In Scala, is there any difference at all between Nil and List() ?
3 Answers
3
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How can I use if/else in a dictionary comprehension?
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@Marcin's answer covers it all, but just in case someone wants to see an actual example, I add two below:
Let's say you have the following dictionary of sets
d = {'key1': {'a', 'b', 'c'}, 'key2': {'foo', 'bar'}, 'key3': {'so', 'sad'}}
and you want ...
How to open a new window on form submit
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No need for Javascript, you just have to add a target="_blank" attribute in your form tag.
<form target="_blank" action="http://example.com"
method="post" id="mc-embedded-subscribe-form"
name="mc-embedded-subscribe-form" class="validate"
>
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How do I run a single test with Nose in Pylons
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nosetests appname.tests.functional.test_controller should work, where the file is named test_controller.py.
To run a specific test class and method use a path of the form module.path:ClassNameInFile.method_name, that is, with a colon separating the module/file pa...
importing pyspark in python shell
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If it prints such error:
ImportError: No module named py4j.java_gateway
Please add $SPARK_HOME/python/build to PYTHONPATH:
export SPARK_HOME=/Users/pzhang/apps/spark-1.1.0-bin-hadoop2.4
export PYTHONPATH=$SPARK_HOME/python:$SPARK_HOME/python/build:$PYTHONPATH
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lenses, fclabels, data-accessor - which library for structure access and mutation is better
...f these libraries also provide a bunch of extra combinators on top, and usually some form of template haskell machinery to automatically generate lenses for the fields of simple record types.
With that in mind, we can turn to the different implementations:
Implementations
fclabels
fclabels is pe...
Why won't my PHP app send a 404 error?
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Your code is technically correct. If you looked at the headers of that blank page, you'd see a 404 header, and other computers/programs would be able to correctly identify the response as file not found.
Of course, your users are still SOL. N...
Get the full URL in PHP
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Have a look at $_SERVER['REQUEST_URI'], i.e.
$actual_link = "http://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";
(Note that the double quoted string syntax is perfectly correct)
If you want to support both HTTP and HTTPS, you can use
$act...
How to get RelativeLayout working with merge and include?
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This is really easier, less hardcoded, and more optimized solution than packing <include/> into another layout. Think what would you do if you would work with lists.
– teoREtik
Feb 2 '12 at ...
What are the differences between a multidimensional array and an array of arrays in C#?
...t32 'value') cil managed
{
// Code size 7 (0x7)
.maxstack 8
IL_0000: ldarg.0
IL_0001: ldarg.1
IL_0002: ldelem.ref
IL_0003: ldarg.2
IL_0004: ldarg.3
IL_0005: stelem.i4
IL_0006: ret
} // end of method Program::SetElementAt
.method private hidebysig static void SetElem...