Translating lm.object to SQL, C, etc function

On Fri, 14 Feb 2003 j+rhelp at howard.fm wrote:

Thanks for the suggestion. After my last post I tried switching from
SPLUS to R and discovered the useful xlevels attribute, which when output

Eh?  S-PLUS has an "xlevels" attribute, but R has an "xlevels" component
(speaks the author of both).

You add methods to functions, not classes, in R.  You could indeed add
generic accessor functions with lm methods, but their absence (and the
lack of documentation of the internal structure) should alert you to the
idea that this is internal structure and not part of a public API.

In SPLUS I came across a useful attribute 'assign', which has a mapping
of term names to variables - the same attribute in R doesn't appear to
provide this information. Is this available somewhere?

Both have an assign *component*, not attribute.  R has a mapping from
model.matrix columns to terms in its assign component: that's not an
accurate description of S-PLUS's component ....