if((rc = mx_expand(mx_rewritel(m,
"index", make_index(n),
"parity", n % 2 ? "odd" : "even",
if((rc = mx_expand(mx_rewritel(m,
"index", make_index(n),
"parity", n % 2 ? "odd" : "even",
"first", n == 0 ? "true" : "false",
"last", n + 1 == ntracks ? "false" : "true",
"sort", e[n].sort,
"first", n == 0 ? "true" : "false",
"last", n + 1 == ntracks ? "false" : "true",
"sort", e[n].sort,