Re: How can I parse arguments of an expression unevaluated?
- To: mathgroup at smc.vnet.net
- Subject: [mg100938] Re: [mg100894] How can I parse arguments of an expression unevaluated?
- From: Oliver Ruebenkoenig <ruebenko at wolfram.com>
- Date: Thu, 18 Jun 2009 06:19:23 -0400 (EDT)
- References: <200906180848.EAA19681@smc.vnet.net>
Erich,
On Thu, 18 Jun 2009, Erich Neuwirth wrote:
> What I would like to have is the following:
> I want to give the expression
> MyFunArgs[1, 2, a = 3, b = 4]
> and I would like to get 3 lists,
> the first list has all the arguments which are
> not written as an assignment, {1,2}
> The second list should be a list of strings
> with the names of the variables to be assignes
> {"a","b"}
> and the third list should be the values to be assigned:
> {3,4}
>
> so
> MyFunArgs[1, 2, a = 3, b = 4]
> should produce
> {{1,2},{"a","b"},{3,4}}
>
> How can I accomplish this?
>
>
>
try:
SetAttributes[MyFunArgs, HoldAll]
MyFunArgs[x_, y_, Set[v1_, w1_], Set[v2_, w2_]] := {{x, y},
ToString /@ {v1, v2}, {w1, w2}}
MyFunArgs[1, 2, a = 3, b = 4]
This only works if a and b are symbols.
Oliver
- References:
- How can I parse arguments of an expression unevaluated?
- From: Erich Neuwirth <erich.neuwirth@univie.ac.at>
- How can I parse arguments of an expression unevaluated?