emptyniltrueemptyconsxyfalsetailnilniltailconsxyyheadconsxyxzero0truezerosxfalsep00ps00pssxspsxintlistxif_intlistemptyxxif_intlisttruexnilif_intlistfalsexconssheadxintlisttailxintxyif_intzeroxzeroyxyif_inttruebxyif1bxyif_intfalsebxyif2bxyif1truexycons0nilif1falsexycons0ints0yif2truexynilif2falsexyintlistintpxpyempty1nil0true0cons2false0tail1head1zero100s1p1intlist1if_intlist2int2if_int4if13if23FULL./TRS/SchneiderKamp/trs/thiemann14.trs