[boost] [Review] Named parameter questions

From: Thomas Witt (witt_at_[hidden])
Date: 2004-11-23 01:21:19

Hi,

I was going to provide a (late) review for the named parameter lib, but 
I have some questions before I can do that.

1) I find the use of the name "keyword" for the type of the named 
parameter somehow odd. It does not seem to fit with what I associate 
with keywords. What's the rationale behind that choice.

2) The docs give the following example for mixing named and positional 
  parameters:

foo("bar", 3.14f);
foo(value = 6.28f, "baz")

Should print:

bar = 3.14
baz = 6.28

I believe the parameter deduction in this case is too smart. Is there a 
way for the user of the library to enforce a rule like "No positional 
param after named params" on a case by case basis?

3) Section 5 has the following example

// implementation of bar()
template <class Params>
void bar_impl(Params const& params)
{
     // Extract arguments
     float x_ = params[x];
     float theta_ = params[theta | pi];
     float span = params[span || boost::bind(default_span, x_, theta_)];
     //!!  ^^^^          ^^^^
     ...
}

IIUC this does not work. I assume the second span should refer to a 
named paramter object. I think it refers to the local span object.
Did I miss something?

Regards

Thomas

PS: Doug I know I am late, feel free to ignore me.

-- 
Thomas Witt
witt_at_[hidden]