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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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List of foreign keys and the tables they reference
...key is described in the columns r_owner and r_constraint_name of the table ALL_CONSTRAINTS. This will give you the info you want:
SELECT a.table_name, a.column_name, a.constraint_name, c.owner,
-- referenced pk
c.r_owner, c_pk.table_name r_table_name, c_pk.constraint_name r_pk
FROM...
How can I have a newline in a string in sh?
...rom the Bash manual page:
Words of the form $'string' are treated specially. The word expands to
string, with backslash-escaped characters replaced as specified by the
ANSI C standard. Backslash escape sequences, if present, are decoded
as follows:
\a alert (bell)
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How do I pass values to the constructor on my wcf service?
... How can I use it for self hosting? I receive an exception after calling to CreateServiceHost. I can only call to the protected method public override ServiceHostBase CreateServiceHost(string constructorString, Uri[] baseAddresses); The exception is The exception message was: 'ServiceHostF...
Error to run Android Studio
I have installed Android Studio and I followed all steps described here
17 Answers
17...
How to compile python script to binary executable
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Or use PyInstaller as an alternative to py2exe. Here is a good starting point. PyInstaller also lets you create executables for linux and mac...
Here is how one could fairly easily use PyInstaller to solve the issue at hand:
pyinstall...
No mapping found for field in order to sort on in ElasticSearch
... I still have the problem but I want the documents to be in the results in all cases even if they don't have the attribute.
– c4k
Oct 27 '13 at 15:47
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How to change a django QueryDict to Python Dict?
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In Django 1.8 on Python 3 all I needed was dict(queryDict).
– fmalina
May 15 '15 at 19:16
1
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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 ...
How do I convert a String object into a Hash object?
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The string created by calling Hash#inspect can be turned back into a hash by calling eval on it. However, this requires the same to be true of all of the objects in the hash.
If I start with the hash {:a => Object.new}, then its string represen...