[Python-Dev] [Python-checkins] peps: New DSL syntax and slightly changed semantics for the Argument Clinic DSL.

[Stefan Krah]

Larry Hastings <larry at hastings.org> wrote:
> * The DSL currently makes no provision for specifying per-parameter
>   type annotations.  This is something explicitly supported in Python;
>   it should be supported for builtins too, once we have reflection support.
> 
>   It seems to me that the syntax for parameter lines--dictated by
>   Guido--suggests conversion functions are themselves type annotations.
>   This makes intuitive sense.

Really, did you read PEP 437? It's all in there.


>  But my thought experiments in how to convert the conversion function
>  specification into a per-parameter type annotation ranged from obnoxious
>  to toxic; I don't think that
>  line of thinking will bear fruit.

Did you look at the patch that I posted in issue #16612? It's already
implemented:

$ ./printsemant Tools/preprocess/testcases/posix_stat.c
PROGRAM[
  SOURCE[...],
  DEFINE[
    CNAME posix_stat,
    SPEC[
      DECLARATION
         { fun_fqname = os.stat,
           fun_name = stat,
           fun_cname = posix_stat,
           fun_kind = Keywords,
           fun_params = [
             { param_name = path,
               param_type = [bytes, int, str],     <== here it is
               param_default = NONE,
               param_kind = (PosOrKwd, Required),
               param_conv = path_converter,
               param_parseargs = [
                 ConvArg { arg_name = path_converter,
                           arg_type = int (*converter)(PyObject *, void *)
                           arg_use_ptr = false },
                 MainArg { arg_name = path,
                           arg_type = path_t,
                           arg_use_ptr = true }]},
[...]



Stefan Krah