Groups > comp.lang.python > #20545

Re: Generating class definitions at runtime in memory from XSD or JSON

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From	Nobody <nobody@nowhere.com>
Subject	Re: Generating class definitions at runtime in memory from XSD or JSON
Date	Fri, 17 Feb 2012 10:02:27 +0000
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On Thu, 16 Feb 2012 17:15:59 -0800, Stodge wrote:

> Does anyone know of a library to generate class definitions in memory,
> at runtime, from XSD or JSON? I know about PyXB, generateDS and some
> others, but they all rely on generating python source files at the
> command line, and then using those to parse XML.

You don't need a library to generate classes. If the type() function is
called with 3 arguments, it creates and returns a new class. The first
argument is the name of the class, the second argument a tuple of base
classes, the third argument is the class' dictionary. E.g.:

	class Foo(Bar, Baz):
	    def __init__(self):
	        pass

could be written as:

	def foo_init(self):
	    pass

	Foo = type('Foo', (Bar, Baz), {'__init__': foo_init})

If you want to generate the function bodies from the contents of the
JSON or XML file, use exec().

Thread

Generating class definitions at runtime in memory from XSD or JSON Stodge <stodge@gmail.com> - 2012-02-16 17:15 -0800
  Re: Generating class definitions at runtime in memory from XSD or JSON Nobody <nobody@nowhere.com> - 2012-02-17 10:02 +0000
  Re: Generating class definitions at runtime in memory from XSD or JSON Stefan Behnel <stefan_ml@behnel.de> - 2012-02-17 13:57 +0100

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