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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' :...
What is the combinatory logic equivalent of intuitionistic type theory?
...------------ S ={beta} T
G |- x : S G |- s : T
In a small variation from the original, I've made lambda the only binding operator, so the second argument of Pi should be a function computing the way the return type depends on the input. By convention (e.g. in Agda, but sadly not...
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 ...
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, \
$(call __check_defined,$...
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 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 ...
“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):
...
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.
...