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Confused by python file mode “w+”
...to the top of the file before reading, otherwise you'll just read an empty string
data = f.read() # Returns 'somedata\n'
Note the f.seek(0) -- if you forget this, the f.read() call will try to read from the end of the file, and will return an empty string.
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What's a concise way to check that environment variables are set in a Unix shell script?
...st variant (using just ?) requires STATE to be set, but STATE="" (an empty string) is OK — not exactly what you want, but the alternative and older notation.
The second variant (using :?) requires DEST to be set and non-empty.
If you supply no message, the shell provides a default message.
The ${v...
How can I add (simple) tracing in C#? [closed]
...at was tracing using the TraceSource.TraceEvent(TraceEventType, Int32, String) method where the TraceSource object was initialised with a string making it a 'named source'.
For me the issue was not creating a valid combination of source and switch elements to target this source. Here is an exam...
Calling generic method with a type argument known only at execution time [duplicate]
...pe arguments... Are you trying to call
Method<MyNamespace.Interface<string>>(); // (Or whatever instead of string)
or
Method<MyNamespace.Interface>();
If it's the latter, you only need a call to MakeGenericMethod - not MakeGenericType.
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Initialise a list to a specific length in Python [duplicate]
...th [['' for i in range(5)] for j in range(5)] instead of >>> card_strings = [['']*5]*5 >>> card_strings[0][0] = "Well that was unexpected..."
– RobotHumans
Sep 19 '15 at 9:18
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Oracle SQL escape character (for a '&')
...s gets the job done, but is a little clunky when dealing with pre-existing strings.
– aglassman
Sep 5 '13 at 14:43
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Printing Python version in output
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import sys
print(sys.version)
This prints the full version information string. If you only want the python version number, then Bastien Léonard's solution is the best. You might want to examine the full string and see if you need it or portions of it.
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How to create new folder? [duplicate]
...use the local rules of the python installation running the script for path strings. Using os.path.join in all cases assures that your paths will be formed correctly for the platform the script is being run on.
– Alan Leuthard
Jun 13 '17 at 21:12
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IndexOf function in T-SQL
... an email address column, I need to find the position of the @ sign for substringing.
4 Answers
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php Replacing multiple spaces with a single space [duplicate]
...here a way to get rid of all spaces at the right & and the left of the string? for example, " a b c ", would be "a b c", I know we could use trim($output), but it would be nice to have it in regex
– eawedat
Feb 1 '17 at 22:31
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