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How do I concatenate or merge arrays in Swift?
...ith Sequence's flatMap(_:) method
Swift provides a flatMap(_:) method for all types that conform to Sequence protocol (including Array). flatMap(_:) has the following declaration:
Returns an array containing the concatenated results of calling the given transformation with each element of this ...
Is it possible to forward-declare a function in Python?
...rwards is impossible, what about defining it in some other module?
Technically you still define it first, but it's clean.
You could create a recursion like the following:
def foo():
bar()
def bar():
foo()
Python's functions are anonymous just like values are anonymous, yet they can be ...
How to change the type of a field?
...(x)) and then save the document again.
If you need to do this programmatically and entirely from the shell, you can use the find(...).forEach(function(x) {}) syntax.
In response to the second comment below. Change the field bad from a number to a string in collection foo.
db.foo.find( { 'bad' :...
Abort makefile if variable not set
... an auxiliary function for that:
# Check that given variables are set and all have non-empty values,
# die with an error otherwise.
#
# Params:
# 1. Variable name(s) to test.
# 2. (optional) Error message to print.
check_defined = \
$(strip $(foreach 1,$1, \
$(call __check_defined,$...
What is the type of lambda when deduced with “auto” in C++11?
...
The type of a lambda expression is unspecified.
But they are generally mere syntactic sugar for functors. A lambda is translated directly into a functor. Anything inside the [] are turned into constructor parameters and members of the functor object, and the parameters inside () are turned ...
“ImportError: No module named” when trying to run Python script
...the notebook to operate from in your ipython_notebook_config.py file (typically using the c.NotebookManager.notebook_dir setting).
The solution is to provide the python interpreter with the path-to-your-module. The simplest solution is to append that path to your sys.path list. In your notebook, fi...
Team city unmet requirement: MSBuildTools12.0_x86_Path exists
I have a TeamCity install on x32 Server2008 windows machine. I've run the .net 4.5 web install. I've also copied over the files from my x64 machine based on this article so that I didn't need to install vs2012 (though, I did have the change the path to remove x86 on the 32bit machine):
...
Rspec doesn't see my model Class. uninitialized constant error
...
Your spec_helper file is missing some important commands. Specifically, it's not including config/environment and initializing rspec-rails.
You can add the following lines to the start of your spec/spec_helper.rb file
ENV["RAILS_ENV"] ||= 'test'
require File.expand_path("../../config/envi...
How to get Linux console window width in Python
Is there a way in python to programmatically determine the width of the console? I mean the number of characters that fits in one line without wrapping, not the pixel width of the window.
...
How to use custom packages
...something very obvious but I cannot find much information about this. Basically, I have these two files in the same folder:
...