LFUN
  #include <classes.h>

  string * RemoveClassId (string id)
  string * RemoveClassId (string * id)

DESCRIPTION
  Remove one or more id strings from this object's P_CLASS_IDS.

  Argument:
    id: a single string, or an array of strings to remove.

  Result: P_CLASS_IDS' new content.

EXAMPLE
  RemoveClassId("button");
  RemoveClassId(C_WEAPON);

IMPLEMENTED
  /std/thing/description