rc_setup_context 1578 src/regexp.c           obj = rc_setup_context(ctx, SCM_CAR(sp));
rc_setup_context 1588 src/regexp.c           SCM_APPEND1(head, tail, rc_setup_context(ctx, SCM_CAR(sp2)));
rc_setup_context 1636 src/regexp.c       ast = rc_setup_context(&cctx, ast);