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How do I get only directories using Get-ChildItem?
I'm using PowerShell 2.0 and I want to pipe out all the subdirectories of a certain path. The following command outputs all files and directories, but I can't figure out how to filter out the files.
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Deep null checking, is there a better way?
...'d say
cake?.frosting?.berries?.loader
and the compiler would generate all the short-circuiting checks for you.
It didn't make the bar for C# 4. Perhaps for a hypothetical future version of the language.
Update (2014):
The ?. operator is now planned for the next Roslyn compiler release. Note ...
django unit tests without a db
... doesn't require the db to set up. And while it is fast to setup a db, I really don't need it in some situations.
11 Answer...
Can you split a stream into two streams?
... @JoD It is thread-safe if heads and tails are thread-safe. Additionally, assuming the use of non-parallel streams, only the order is not guaranteed, so they are thread-safe. It's up to the programmer to fix concurrency issues, so this answer is perfectly suitable if the collections are threa...
What does the “map” method do in Ruby?
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Ahhh I get it. So .map actually mutates the array while .each just loops through the array to access the values while leaving the original array untouched?
– bigpotato
Aug 23 '12 at 4:18
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Converting string from snake_case to CamelCase in Ruby
...equire "active_support/core_ext/string" is suffice, providing Rails is installed already.
– Masa Sakano
Jun 23 '18 at 2:03
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Why doesn't nodelist have forEach?
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NodeList now has forEach() in all major browsers
See nodeList forEach() on MDN.
Original answer
None of these answers explain why NodeList doesn't inherit from Array, thus allowing it to have forEach and all the rest.
The answer is found on this es-discus...
How to convert an array of strings to an array of floats in numpy?
...(or equivalently, use a list comprehension). (In Python 3, you'll need to call list on the map return value if you use map, since map returns an iterator now.)
However, if it's already a numpy array of strings, there's a better way. Use astype().
import numpy as np
x = np.array(['1.1', '2.2', '3....
Best practices for in-app database migration for Sqlite
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I maintain an application that periodically needs to update a sqlite database and migrate old databases to the new schema and here's what I do:
For tracking the database version, I use the built in user-version variable that sqlite provides (sqlite does nothing w...
Integrating MySQL with Python in Windows
...rrently, I would recommend using PyMySQL. It's pure python, so it supports all OSes equally, it's almost a drop-in replacement for mysqldb, and it also works with python 3. The best way to install it is using pip. You can install it from here (more instructions here), and then run:
pip install pymy...