change of behaviour?

[progman1]

hi

I have a ppx that was working under 0.20 and now exhibits different
behaviour under 0.24

my extension processor is defined thus:

let expand ~loc ~path (e : expression) =
...

let ext=
  Extension.declare
    "pr"
    Extension.Context.expression
    Ast_pattern.(pstr ((pstr_eval __ nil) ^:: nil))
    expand

under 0.20 the path passed to expand looked like:

lib/myfile.ml

but under 0.24 it is:

lib/myfile.ml.Map

where did ".Map" come from?!