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Use cases for the 'setdefault' dict method
...e case: Grouping items (in unsorted data, else use itertools.groupby)
# really verbose
new = {}
for (key, value) in data:
if key in new:
new[key].append( value )
else:
new[key] = [value]
# easy with setdefault
new = {}
for (key, value) in data:
group = new.setdefault(k...
How can I calculate the difference between two dates?
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Not all days have 86400 seconds. For a trivial example that's fine but it's not a good idea in the real world. DST changes, leap seconds, etc can all mess with it. NSCalendar can tell you how many seconds are in a given day.
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'\r': command not found - .bashrc / .bash_profile [duplicate]
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When all else fails in Cygwin...
Try running the dos2unix command on the file in question.
It might help when you see error messages like this:
-bash: '\r': command not found
Windows style newline characters can cause issues ...
Can you make just part of a regex case-insensitive?
...ase-insensitive by using the (?i:) pattern modifier.
Modern regex flavors allow you to apply modifiers to only part of the regular expression. If you insert the modifier (?ism) in the middle of the regex, the modifier only applies to the part of the regex to the right of the modifier. You can turn ...
Why does Hibernate require no argument constructor?
...objects without invoking the constructor. But this is not available across all VMs. For example, XStream can create instances of objects that don't have a public no-arg constructor, but only by running in a so-called "enhanced" mode which is available only on certain VMs. (See the link for details.)...
How to split a string into a list?
...d, it might be a typo, but you have your loop a little messed up. If you really did want to use append, it would be:
words.append(word)
not
word.append(words)
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Where does the @Transactional annotation belong?
...r their methods or is it better to annotate the Service classes which are calling using the DAO objects? Or does it make sense to annotate both "layers"?
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Get escaped URL parameter
... you may want "decodeURIComponent()" instead of "decodeURI()", especially if you are passing interesting data like return URLs in as a URL parameter
– perfectionist
Feb 27 '12 at 13:14
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Should I inherit from std::exception?
... just catch the std::exception.
Edit: as Martin and others noted, you actually want to derive from one of the sub-classes of std::exception declared in <stdexcept> header.
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Javascript: negative lookbehind equivalent?
... 79.0
✔️ Node.js 6.0 behind a flag and 9.0 without a flag
✔️ Deno (all versions)
✔️ SpiderMonkey
✔️ Mozilla Firefox 78.0
????️ JavaScriptCore: Apple is working on it
????️ Apple Safari
????️ iOS WebView (all browsers on iOS + iPadOS)
❌ Chakra: Microsoft was working on ...