On 4/11/07, Tony Lownds email@example.com wrote:
Function annotations PEP is accepted and code has been checked in to p3yk. I don't think there would be much support for the syntax in 2.6, but I could be wrong. A more palatable compatibility strategy may be to introduce a decorator that sets function.__annotations__, so that these two function definitions would have equivalent annotations:
@annotate(int, int, returns=int)
... def gcd1(m, n): ... etc
def gcd2(m: int, n: int) -> int:
It's easier for a decorator to be compatible with run-time semantics, and more likely to avoid syntax questions, than embedding the annotattions in docstrings. Source code conversion (2to3) could change the @annotate decorator form to the in-line function form. Tools could be written to use either annotation set.
What do y'all think?
Speaking only to the part about 2to3, that sort of conversion would be a pain in the ass to write. Even if the @annotate decorator were keyword-args only (allowing positional args complicates the implementation more than you would expect), it would still probably be quicker/easier/more accurate just to port the 3.0 annotations implementation to 2.6.