Am 7 May 2006 um 12:38 hat Robert Dodier geschrieben:
> Hello,
>
> At present the functions op and args barf on atoms.
> I propose that op and args return false when the argument is an atom.
>
> This change is intended to obviate the need to always test whether
> the argument is an atom before calling op or args.
>
> I looked at the commercial Macsyma documentation, but it didn't
> say what op and args do when the argument is an atom.
>
> Comments?
>
> Robert Dodier
Hi Robert,
generally a good idea. I would be nice to have a return value instead of an error.
What is the advantage of returning false? Another possibility would be
op(<atom>); --> < identity function>
args(<atom>); --> <atom>
Example:
map( 'args, [ a, b^2 ] ); --> [ [a], [b,2] ]
Volker