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Python: most idiomatic way to convert None to empty string?
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If you actually want your function to behave like the str() built-in, but return an empty string when the argument is None, do this:
def xstr(s):
if s is None:
return ''
return str(s)
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Is “else if” a single keyword?
...er to Can you start a class name with a numeric digit? that spaces are not allowed in identifiers and so therefore else if can not be a single keyword but must be two separate keywords.
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impr...
How are GCC and g++ bootstrapped?
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(optional) repeat step 2 for verification purposes.
This process is called bootstrapping. It tests the compiler's capability of compiling itself and makes sure that the resulting compiler is built with all the optimizations that it itself implements.
EDIT: Drew Dormann, in the comments, point...
Is there any difference between “foo is None” and “foo == None”?
... Hmmm, I think your link changed, unless you were interested in how to call external functions from python
– Pat
May 4 '12 at 20:39
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How to make rounded percentages add up to 100%
...55310199789695, 8.780231335436383, 8.04416403785489, 0]. The last one logically returns -1. I thought of the following solution really quickly but there's probably something better: jsfiddle.net/0o75bw43/1
– Cruclax
Aug 5 '16 at 16:39
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Python string.join(list) on object array rather than string array
...riments says that the list comprehension one can be a good 60% faster on small lists (experiment run 10^6 times on a list of three object()s). However, their performance is similar on big lists (2nd experiment run once on a 10^7 objects() list).
– gozzilli
Mar ...
django admin - add custom form fields that are not part of the model
... ModelForm class and then declare your extra fields inside that as you normally would. I've also given an example of how you might use these values in form.save():
from django import forms
from yourapp.models import YourModel
class YourModelForm(forms.ModelForm):
extra_field = forms.CharFiel...
Characters allowed in a URL
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The characters allowed in a URI are either reserved or unreserved (or a percent character as part of a percent-encoding)
http://en.wikipedia.org/wiki/Percent-encoding#Types_of_URI_characters
says these are RFC 3986 unreserved characters ...
Swift: #warning equivalent
...builds clean in production, but I get a warning in development that essentially reminds me I'm in dev mode - using different URLs, timeouts, other settings etc. Arie's suggestion above lets me do this, your technique just flags everything. That said, this technique has its use for sure so I up voted...
How to find the operating system version using JavaScript?
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If you list all of window.navigator's properties using
console.log(navigator);
You'll see something like this
# platform = Win32
# appCodeName = Mozilla
# appName = Netscape
# appVersion = 5.0 (Windows; en-US)
# language = en-US
# ...