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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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Undefined symbols for architecture arm64
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If your Architectures and Valid Architectures are all right, you may check whether you have added $(inherited) , which will add linker flags generated in pods, to Other Linker Flags as below:
share...
Cross-Origin Request Headers(CORS) with PHP headers
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Access-Control-Allow-Headers does not allow * as accepted value, see the Mozilla Documentation here.
Instead of the asterisk, you should send the accepted headers (first X-Requested-With as the error says).
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Disable migrations when running unit tests in Django 1.7
... syncdb did in 1.6. I defined a new settings module just for unit
tests called "settings_test.py", which imports * from the main
settings module and adds this line:
MIGRATION_MODULES = {"myapp": "myapp.migrations_not_used_in_tests"}
Then I run tests like this:
DJANGO_SETTINGS_MODU...
How to get a variable name as a string in PHP?
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Actually now that I've tested my code, my code always returned 'var' because it's being used in the function. When I use $GLOBALS instead, it returns the correct variable name for some reason. So I'll change the above code to use...
MongoDB/Mongoose querying at a specific date?
...onents. To query those times you need to create a date range that includes all moments in a day.
db.posts.find( //query today up to tonight
{"created_on": {"$gte": new Date(2012, 7, 14), "$lt": new Date(2012, 7, 15)}})
s...
Best way to iterate through a Perl array
...ay elements occurs. ($_ is aliased to the element in #1, but #2 and #3 actually copy the scalars from the array.)
#5 might be similar.
In terms memory usage: They're all the same except for #5.
for (@a) is special-cased to avoid flattening the array. The loop iterates over the indexes of the array...
Remove duplicates from an array of objects in JavaScript
...) dot notation. Yours is ES5 syntax. The others are mostly ES6 (ECMA2015). All are valid in 2017. See jaredwilli's comment.
– agm1984
Nov 15 '17 at 9:20
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C/C++ with GCC: Statically add resource files to executable/library
Does anybody have an idea how to statically compile any resource file right into the executable or the shared library file using GCC?
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Why is there no xrange function in Python3?
...Some performance measurements, using timeit instead of trying to do it manually with time.
First, Apple 2.7.2 64-bit:
In [37]: %timeit collections.deque((x for x in xrange(10000000) if x%4 == 0), maxlen=0)
1 loops, best of 3: 1.05 s per loop
Now, python.org 3.3.0 64-bit:
In [83]: %timeit collec...