RE: [boost] Named function params

From: Paul A. Bristow (boost_at_[hidden])
Date: 2003-10-10 14:37:55

| -----Original Message-----
| From: boost-bounces_at_[hidden]
| [mailto:boost-bounces_at_[hidden]]On Behalf Of David Abrahams
| Sent: Sunday, October 05, 2003 9:57 PM
| To: boost
| Subject: [boost] Named function params

| In an attempt to improve on the interface used by the Boost.Graph
| library for named parameters, I came up with the enclosed scheme,
| which allows the following Python-like syntax:
|
|
|   int x1 = f("x", 3.14, 22);
|   int x2 = f(value = 3.14, name = "x");
|   int x3 = f(value = 6.5);
|   int x4 = f();
|
|   int x5 = g("x", 3.14, 22);
|   int x6 = g(value = 3.14, name = "x");
|
|   int x8 = g("q", index = 77);
|
| I'm pretty proud of myself (;->) but I'm not too satisfied with how
| much code is required for someone wanting to write a new function
| accepting keyword arguments, and further I'm not sure how to design a
| good interface for automatically generating the boilerplate with the
| preprocessor.  Consider that there may be initial non-keyword args,
| which might themselves be templated or not.
|
| I thought I'd open it up for suggestions.  Thoughts, anyone?

Impressive - but won't this delay enhancement of the C++ language to add some
proper way of doing this?  Named parameters is hardly a novel concept.

Or have we accepted this C++ is already fossilised?

Paul