Hi All,
This is my first post to python-dev so I will briefly introduce myself: My
name is Rob Cliffe and I am a commercial programmer living in London, UK. I
have some 30 years of programming experience but have only been using Python
for a couple of years.
First I want to say what a fantastic language Python is. It is THE best
language for development in my opinion, and a joy to use.
My specific issue:
I eventually got my head round decorator syntax and realised that what came
after the '@' was (basically) a function that took a function as argument and
returned a function as result.
However it seems to me unPythonesque (i.e. an exception to Python's normal
consistency) that the syntax of what follows the '@' should be restricted to
either a single (function) identifier or a single (function) identifier with an
argument list.
The example I tried, which seems not an unreasonable sort of thing to do, was
along the lines of:
def deco1(func):
<deco1-suite>
def deco2(func):
<deco2-suite>
DecoList = [deco1, deco2]
@DecoList[0] # NO - CAUSES SYNTAX ERROR
def foo():
pass
I am sure other guys have their own examples.
I am of course not the first person to raise this issue, and I see that Guido
has a "gut feeling" against allowing a general expression after the '@'.
BUT - a general expression can be "smuggled in" very easily as a function
argument:
def Identity(x): return x
@Identity(DecoList[0]) # THIS WORKS
def foo():
pass
So - the syntax restriction seems not only inconsistent, but pointless; it
doesn't forbid anything, but merely means we have to do it in a slightly
convoluted (unPythonesque) way. So please, Guido, will you reconsider?
Best wishes
Rob Cliffe_______________________________________________
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