break
		}
		for ( ; s; s = s.next) {

			// if the symbol has no sequence weight
			// and if there a time skip,
			// add a sequence marker before it
			if (((!w_tb[s.type] && s.type != C.STAVES)
			  || s.type == C.SPACE || s.type == C.GRACE)
			if ((((!w_tb[s.type] && s.type != C.STAVES)
			  || s.type == C.SPACE)
			 && s.time			// not at start of tune
			 && (!s.prev || s.time > s.prev.time + s.prev.dur)) {
			 && (!s.prev || s.time > s.prev.time + s.prev.dur))
			|| (s.type == C.GRACE		// n {gn} {gn} n
			 && s.prev && s.prev.type == C.GRACE)) {
				s2 = {
					type: C.SM,
					v: s.v,
					p_v: s.p_v,
					time: s.time,
					dur:0,
					next: s,