howto redirect and extend help content ?

[Rob Wolfe]

Stef Mientki <S.Mientki-nospam at mailbox.kun.nl> writes:

> I'm making special versions of existing functions,
> and now I want the help-text of the newly created function to exists of
> 1. an extra line from my new function
> 2. all the help text from the old function
>
> # the old function
> def triang(M,sym=1):
>      """The M-point triangular window.    <== old help text
>      """
>      ....
>
> # the new function
> def chunked_triang(M):
>      """ Chunked version of "triang"      <== the extra line
>      """
>
>  >>> help(chunked_triang)
> # should give something like
>
> chunked_triang(M)                        <== the new definition
>      Chunked version of "triang"          <== the extra line
>      The M-point triangular window.       <== old help text
>
> Is that possible ?

You can take advantage of the decorator syntax:

>>> def triang(M,sym=1):
...     """The M-point triangular window.
...     """
...     return "triang"
... 
>>> help(triang)
Help on function triang in module __main__:

triang(M, sym=1)
    The M-point triangular window.

>>> def add_doc(f):
...     def wrap(g):
...             g.__doc__="chunked version of %s\n%s" % (f.__name__,f.__doc__)
...             return g
...     return wrap
... 
>>> @add_doc(triang)
... def chunked_triang(M):
...     return "chunked triang"
... 
>>> help(chunked_triang)
Help on function chunked_triang in module __main__:

chunked_triang(M)
    chunked version of triang
    The M-point triangular window.

-- 
HTH,
Rob