nix-super/src/fix-ng/fix-expr.cc

#include "fix-expr.hh"
#include "expr.hh"


ATerm bottomupRewrite(TermFun & f, ATerm e)
{
    e = f(e);

    if (ATgetType(e) == AT_APPL) {
        AFun fun = ATgetAFun(e);
        int arity = ATgetArity(fun);
        ATermList args = ATempty;

        for (int i = arity - 1; i >= 0; i--)
            args = ATinsert(args, bottomupRewrite(f, ATgetArgument(e, i)));
        
        return (ATerm) ATmakeApplList(fun, args);
    }

    if (ATgetType(e) == AT_LIST) {
        ATermList in = (ATermList) e;
        ATermList out = ATempty;

        while (!ATisEmpty(in)) {
            out = ATinsert(out, bottomupRewrite(f, ATgetFirst(in)));
            in = ATgetNext(in);
        }

        return (ATerm) ATreverse(out);
    }

    return e;
}