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Nested classes' scope?
I'm trying to understand scope in nested classes in Python. Here is my example code:
6 Answers
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Is Meyers' implementation of the Singleton pattern thread safe?
Is the following implementation, using lazy initialization, of Singleton (Meyers' Singleton) thread safe?
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Why is it slower to iterate over a small string than a small list?
I was playing around with timeit and noticed that doing a simple list comprehension over a small string took longer than doing the same operation on a list of small single character strings. Any explanation? It's almost 1.35 times as much time.
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How to limit the maximum value of a numeric field in a Django model?
Django has various numeric fields available for use in models, e.g. DecimalField and PositiveIntegerField . Although the former can be restricted to the number of decimal places stored and the overall number of characters stored, is there any way to restrict it to storing only numbers within a ...
Is there a reason for C#'s reuse of the variable in a foreach?
When using lambda expressions or anonymous methods in C#, we have to be wary of the access to modified closure pitfall. For example:
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Is there a way to automate the android sdk installation?
...tall the Android SDK and AVD Manager, and then install the APIs, tools through the UI. Is there a way to automate this process?
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Tools to generate database tables diagram with Postgresql? [closed]
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I love schemaspy for schema visualisations. Look at the sample output they provide, and drool. Note the tabs!
You'll need to download the JDBC driver here, then your command should look something like:
java -jar schemaspy-6.0.0-rc2.jar -t pgsql -db datab...
How do I update a Python package?
I'm running Ubuntu 9:10 and a package called M2Crypto is installed (version is 0.19.1). I need to download, build and install the latest version of the M2Crypto package (0.20.2).
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How to list all Git tags?
In my repository, I have created tags using the following commands.
10 Answers
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How do I set a variable to the output of a command in Bash?
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In addition to backticks `command`, command substitution can be done with $(command) or "$(command)", which I find easier to read, and allows for nesting.
OUTPUT=$(ls -1)
echo "${OUTPUT}"
MULTILINE=$(ls \
-1)
echo "${MULTILINE}"
Quoting (") does matter to preserv...