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Officially, what is typename for?
On occasion I've seen some really indecipherable error messages spit out by gcc when using templates... Specifically, I've had problems where seemingly correct declarations were causing very strange compile errors that magically went away by prefixing the typename keyword to the beginning of the...
How can I count the occurrences of a list item?
Given an item, how can I count its occurrences in a list in Python?
25 Answers
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Items in JSON object are out of order using “json.dumps”?
...thon 3.6, the keyword argument order is preserved and the above can be rewritten using a nicer syntax:
>>> json.dumps(OrderedDict(a=1, b=2))
'{"a": 1, "b": 2}'
>>> json.dumps(OrderedDict(b=2, a=1))
'{"b": 2, "a": 1}'
See PEP 468 – Preserving Keyword Argument Order.
If your in...
Best way to test if a row exists in a MySQL table
I'm trying to find out if a row exists in a table. Using MySQL, is it better to do a query like this:
12 Answers
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__getattr__ on a module
...le, use a module as a context manager simply by defining __enter__ and __exit__, before those tricks broke.
Recently some historical features have made a comeback, the module __getattr__ among them, and so the existing hack (a module replacing itself with a class in sys.modules at import time) sho...
Python error “ImportError: No module named”
...ed on your comments to orip's post, I guess this is what happened:
You edited __init__.py on windows.
The windows editor added something non-printing, perhaps a carriage-return (end-of-line in Windows is CR/LF; in unix it is LF only), or perhaps a CTRL-Z (windows end-of-file).
You used WinSCP to c...
How to use shared memory with Linux in C
I have a bit of an issue with one of my projects.
5 Answers
5
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What is the expected syntax for checking exception messages in MiniTest's assert_raises/must_raise?
What is the expected syntax for checking exception messages in MiniTest's assert_raises / must_raise ?
4 Answers
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JPA or JDBC, how are they different?
I am learning Java EE and I downloaded the eclipse with glassfish for the same. I saw some examples and also read the Oracle docs to know all about Java EE 5. Connecting to a database was very simple. I opened a dynamic web project, created a session EJB , I used EntityManager and with the get meth...
Setting the default value of a DateTime Property to DateTime.Now inside the System.ComponentModel De
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You cannot do this with an attribute because they are just meta information generated at compile time. Just add code to the constructor to initialize the date if required, create a trigger and handle missing values in the database, or implement ...