more stack ops, fix ( in compile mode

include/fh_stack.h

@@ -7,9 +7,37 @@
 #ifndef FORTH_FH_STACK_H
 #define FORTH_FH_STACK_H
 
+enum fh_error ds_roll(struct fh_thread_s *fh, int n);
+
+/** Peek n-th element of data stack */
+enum fh_error ds_peek_n(struct fh_thread_s *fh, uint32_t *out, int n);
+/** Peek n-th element of return stack */
+enum fh_error rs_peek_n(struct fh_thread_s *fh, uint32_t *out, int n);
+/** Peek n-th element of control stack */
+enum fh_error cs_peek_n(struct fh_thread_s *fh, uint32_t *out, int n);
+
+/** Peek top of data stack */
+static inline enum fh_error ds_peek(struct fh_thread_s *fh, uint32_t *out)
+{
+  return ds_peek_n(fh, out, 0);
+}
+
+/** Peek top of return stack */
+static inline enum fh_error rs_peek(struct fh_thread_s *fh, uint32_t *out)
+{
+  return rs_peek_n(fh, out, 0);
+}
+
+/** Peek top of control stack */
+static inline enum fh_error cs_peek(struct fh_thread_s *fh, uint32_t *out)
+{
+  return cs_peek_n(fh, out, 0);
+}
+
 enum fh_error ds_pop(struct fh_thread_s *fh, uint32_t *out);
 enum fh_error rs_pop(struct fh_thread_s *fh, uint32_t *out);
 enum fh_error cs_pop(struct fh_thread_s *fh, uint32_t *out);
+
 enum fh_error ds_push(struct fh_thread_s *fh, uint32_t in);
 enum fh_error rs_push(struct fh_thread_s *fh, uint32_t in);
 enum fh_error cs_push(struct fh_thread_s *fh, uint32_t in);