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Python class inherits object

...erit from object? In Python 3, apart from compatibility between Python 2 and 3, no reason. In Python 2, many reasons. Python 2.x story: In Python 2.x (from 2.2 onwards) there's two styles of classes depending on the presence or absence of object as a base-class: "classic" style classes: the...
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How to format a java.sql Timestamp for displaying?

...er that if SimpleDateFormat object is a local-scoped object (it is created and used only inside a method), then it is thread-safe, since stack on which it will reside is inherently "thread-safe" (as it belongs to a single thread). – quantum Sep 13 '11 at 9:52 ...
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Unit testing code with a file system dependency

...at you clean up after youself -- delete any temporary files you created -- and that you don't accidentally overwrite an existing file that happened to have the same filename as a temporary file you were using. Always use relative paths and not absolute paths. It would also be a good idea to chdir(...
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How to detect if a script is being sourced

... This seems to be portable between Bash and Korn: [[ $_ != $0 ]] && echo "Script is being sourced" || echo "Script is a subshell" A line similar to this or an assignment like pathname="$_" (with a later test and action) must be on the first line of the s...
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When and why will a compiler initialise memory to 0xCD, 0xDD, etc. on malloc/free/new/delete?

...iler will sometimes initialize memory with certain patterns such as 0xCD and 0xDD . What I want to know is when and why this happens. ...
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What is the difference between Collection and List in Java?

What is the difference between Collection and List in Java? When should I use which? 7 Answers ...
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Copy tables from one database to another in SQL Server

I have a database called foo and a database called bar. I have a table in foo called tblFoobar that I want to move (data and all) to database bar from database foo. What is the SQL statement to do this? ...
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How to find gaps in sequential numbering in mysql?

...lues were imported from another system. There is an auto-increment column, and there are no duplicate values, but there are missing values. For example, running this query: ...
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Environment variables for java installation

...A_TOOL_OPTIONS with value -Dfile.encoding="UTF-8". This ensures that Java (and tools such as Maven) will run with a Charset.defaultCharset() of UTF-8 (instead of the default Windows-1252). This has saved a lot of headaches when wirking with my own code and that of others, which unfortunately often a...
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What is the difference between syntax and semantics in programming languages?

What is the difference between syntax and semantics in programming languages (like C, C++)? 10 Answers ...