confusion with decorators
duncan.booth at invalid.invalid
Mon Feb 4 11:19:32 CET 2013
Dave Angel <davea at davea.name> wrote:
> The decorator function will execute while *compiling* the class A, and
> the one in class B is unreferenced.
No, the decorator function is called when *executing* the class body of A.
Compilation could have happened weeks earlier.
It really does make it a lot easier to understand this sort of issue if you
remember that 'class' and 'def' are simply executable statements: the body
of 'class' executes as part of the class definition whenever normal
execution reaches the 'class' statement, the body of 'def' doesn't execute
until the function is called (but default arguments are evaluated when the
'def' is executed).
In both cases however the code is fully compiled whenever the module is
compiled: that could be when the module is imported or if it is __main__
when the script executes, but after the first run of the program all of the
modules (nto the script) will have been compiled once and don't compile
again until the source changes.
Duncan Booth http://kupuguy.blogspot.com
More information about the Python-list