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Capture keyboardinterrupt in Python without try-except
...re some way in Python to capture KeyboardInterrupt event without putting all the code inside a try - except statement?
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What does if __name__ == “__main__”: do?
...ngs:
it sets a few special variables like __name__, and then
it executes all of the code found in the file.
Let's see how this works and how it relates to your question about the __name__ checks we always see in Python scripts.
Code Sample
Let's use a slightly different code sample to explore ho...
detach all packages while working in R
...*) is not necessary but can be useful to prevent the NULL reply from vertically spamming the R window.
(edit: 9/20/2019) In version 3.6.1
It may be helpful to convert loaded only names(sessionInfo()$loadedOnly) to explicitly attached packages first, and then detach the packages, as so.
lapply(names(...
Python hashable dicts
...n algol-like language (as apposed to the syntax free lisp dialects you normally find them in). Because of this, different passes through the input might see different grammars, so cached parse results are invalid, unless I also store the current version of the grammar along with the cached parse re...
What is the most effective way for float and double comparison?
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Be extremely careful using any of the other suggestions. It all depends on context.
I have spent a long time tracing a bugs in a system that presumed a==b if |a-b|<epsilon. The underlying problems were:
The implicit presumption in an algorithm that if a==b and b==c then a==c.
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How to downgrade or install an older version of Cocoapods
How can I downgrade Cocoapods to an older version, or how can I install an older version of Cocoapods?
6 Answers
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How can I detect if the user is on localhost in PHP?
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Which would make this actually easier to break than spoofing the IP. You should really change it.
– Pekka
Jan 13 '10 at 0:09
3
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Recommendations of Python REST (web services) framework? [closed]
...portant in REST, and unless you're very careful about this, you'll end up falling into a REST anti-pattern.
Some frameworks that get it right are web.py, Flask and Bottle. When combined with the mimerender library (full disclosure: I wrote it), they allow you to write nice RESTful webservices:
imp...
Why do some functions have underscores “__” before and after the function name?
...rms using leading or trailing underscores are
recognized (these can generally be combined with any case convention):
_single_leading_underscore: weak "internal use" indicator. E.g. from M import * does not import objects whose name starts with an underscore.
single_trailing_underscore_: ...
Method Resolution Order (MRO) in new-style classes?
...ject'>)
with A forced to come in resolution order only once and after all of its subclasses, so that overrides (i.e., C's override of member x) actually work sensibly.
It's one of the reasons that old-style classes should be avoided: multiple inheritance with "diamond-like" patterns just doesn...