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Why is there “data” and “newtype” in Haskell? [duplicate]
...is actually occurring - its the equivalent of saying case undefined of i -> "ok" (vs. case undefined of D i -> "ok" in the case of data).
– ScootyPuff
Feb 26 '13 at 19:48
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Converting string from snake_case to CamelCase in Ruby
...is what you're looking for.
"active_record".camelize # => "ActiveRecord"
"active_record".camelize(:lower) # => "activeRecord"
If you want to get an actual class, you should use String#constantize on top of that.
"app_user".camelize.constantize
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How to initialize a two-dimensional array in Python?
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Don't use [[v]*n]*n, it is a trap!
>>> a = [[0]*3]*3
>>> a
[[0, 0, 0], [0, 0, 0], [0, 0, 0]]
>>> a[0][0]=1
>>> a
[[1, 0, 0], [1, 0, 0], [1, 0, 0]]
but
t = [ [0]*3 for i in range(3)]
works great.
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Eclipse git checkout (aka, revert)
...this by doing a (hard) reset.
On the project's context menu, select Team > Reset to..., choose "HEAD" and "Hard" as reset type.
Please note that doing this you will lose the changes of ALL files. To revert just a single file see this answer.
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Initialise a list to a specific length in Python [duplicate]
...one. Wound up with [['' for i in range(5)] for j in range(5)] instead of >>> card_strings = [['']*5]*5 >>> card_strings[0][0] = "Well that was unexpected..."
– RobotHumans
Sep 19 '15 at 9:18
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How should I organize Python source code? [closed]
...nality
I use PyDev for eclipse and organise it like I would for Java.
> Workspace
> |
> |-Src
> | |-Package1
> | |-Package2
> | |-main.py
> |-Test
> |-TestPackage1
> |-TestPackage2
Use DocString everywhere to keep trac...
What is the pythonic way to unpack tuples? [duplicate]
... (such as lists) too. Here's another example (from the Python tutorial):
>>> range(3, 6) # normal call with separate arguments
[3, 4, 5]
>>> args = [3, 6]
>>> range(*args) # call with arguments unpacked from a list
[3, 4, 5]
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How do I check if a given Python string is a substring of another one? [duplicate]
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Try using in like this:
>>> x = 'hello'
>>> y = 'll'
>>> y in x
True
share
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improve this answer
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Get the last 4 characters of a string [duplicate]
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Like this:
>>>mystr = "abcdefghijkl"
>>>mystr[-4:]
'ijkl'
This slices the string's last 4 characters. The -4 starts the range from the string's end. A modified expression with [:-4] removes the same 4 characters from ...
Negative list index? [duplicate]
...on. If you use -1 in that case, it returns one element from the last. >>> a = [1,2,3,4,5] >>> a[-1] 5 >>> a[:-1] [1, 2, 3, 4]
– abought
Jul 6 '12 at 20:18
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