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Difference between del, remove and pop on lists
...gt;>> a = [4, 5, 6]
>>> a.remove(7)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ValueError: list.remove(x): x not in list
>>> del a[7]
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
IndexError: lis...
How can I get nth element from a list?
...
Personally I can't comprehend how an at-index accessor that doesn't return a Maybe type is acceptable as idiomatic Haskell. [1,2,3]!!6 will give you a runtime error. It could very easily be avoided if !! had the type [a] -> Int ...
Python exit commands - why so many and when should each be used?
...s functionality was included to help people who do not know Python. After all, one of the most likely things a newbie will try to exit Python is typing in quit.
Nevertheless, quit should not be used in production code. This is because it only works if the site module is loaded. Instead, this fun...
Why does “pip install” inside Python raise a SyntaxError?
... Lennart RegebroLennart Regebro
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2
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Is it safe to parse a /proc/ file?
.../proc/mounts was a consistent snapshot.
For example:
/proc/uptime is totally atomic, as someone mentioned in another answer -- but only since Linux 2.6.30, which is less than two years old. So even this tiny, trivial file was subject to a race condition until then, and still is in most enterpris...
What encoding/code page is cmd.exe using?
...e and other programs
print gibberish, and sometimes they do not.
First of all, Unicode characters will only display if the
current console font contains the characters. So use
a TrueType font like Lucida Console instead of the default Raster Font.
But if the console font doesn’t contain the char...
assertEquals vs. assertEqual in python
... Jarret HardieJarret Hardie
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35
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Serializing object that contains cyclic object value
...e will come here for is debugging their circular objects and there's not really a great way to do that without pulling in a bunch of code, here goes.
One feature that's not as well-known as JSON.stringify() is console.table(). Simply call console.table(whatever);, and it will log the variable in the...
No route matches [GET] /assets
...nment. I ran RAILS_ENV=production rake assets:precompile which generated all of my assets in /public/assets. The problem is that when I start my app w/ RAILS_ENV=production rails s thin I get:
...
How to do an instanceof check with Scala(Test)
I'm trying to incorporate ScalaTest into my Java project; replacing all JUnit tests with ScalaTests. At one point, I want to check if Guice's Injector injects the correct type. In Java, I have a test like this:
...