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setNeedsLayout vs. setNeedsUpdateConstraints and layoutIfNeeded vs updateConstraintsIfNeeded
...ates one of your constraints, you should remove the constraint immediately and call setNeedsUpdateConstraints. In fact, that’s the only case where you should have to trigger a constraint update pass.
In addition, in my experience, I have never had to invalidate constraints, and not set the setNe...
Does Ruby have a string.startswith(“abc”) built in method?
...ot String#startswith: In Ruby, the names of boolean-ish methods end with ? and the words in method names are separated with an _. Not sure where the s went, personally, I'd prefer String#starts_with? over the actual String#start_with?
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Read and overwrite a file in Python
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If you don't want to close and reopen the file, to avoid race conditions, you could truncate it:
f = open(filename, 'r+')
text = f.read()
text = re.sub('foobar', 'bar', text)
f.seek(0)
f.write(text)
f.truncate()
f.close()
The functionality will likely...
How do you log server errors on django sites
...hen playing with the development I can just set settings.DEBUG to True and if an error occures I can see it nicely formatted, with good stack trace and request information.
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Git submodule inside of a submodule (nested submodules)
...t possible for a git submodule to be made of several other git submodules, and the super git repo to fetch the contents for each submodule?
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Css pseudo classes input:not(disabled)not:[type=“submit”]:focus
I want to apply some css for inputs elements and I want to do that only for inputs that are not disabled and are not submit type, below css is not working, maybe if someone can explain me how this must be added .
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Why are `private val` and `private final val` different?
I used to think that private val and private final val are same, until I saw section 4.1 in Scala Reference:
2 Answers
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break out of if and foreach
I have a foreach loop and an if statement. If a match is found i need to ultimately break out of the foreach.
4 Answers
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Why not abstract fields?
...Child constructor would be trying to use a non-existent noargs constructor and that is a compilation error (not a warning).
– Stephen C
Feb 6 '10 at 0:15
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In Firebase, is there a way to get the number of children of a node without loading all the node dat
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The code snippet you gave does indeed load the entire set of data and then counts it client-side, which can be very slow for large amounts of data.
Firebase doesn't currently have a way to count children without loading data, but we do plan to add it.
For now, one solution would be to mai...