#include <stdio.h>
#include <fstream.hfa>
#include <coroutine.hfa>

coroutine RangeParser {
	const char * text;
	int com;
};

void ?{}(RangeParser & this, const char * text) {
	this.text = text;
}

static inline void push(RangeParser & this, int val) { this.com = val; suspend; }
static inline int next(RangeParser & this) { return resume(this).com; }

void main(RangeParser & this) {
	for() {
		int start = -1, stop = -1;
		int start_len = -1, stop_len = -1;
		int ret = sscanf(this.text, "%u%n-%u%n", &start, &start_len, &stop, &stop_len);
		switch(ret) {
		case 0:
			// Not a range, maybe a comma?
			if(this.text[0] == ',') {
				this.text ++;
				continue;
			}

			serr | "Error: unexpected character in next range: '" | this.text |"'";
			exit(2);
		case 1:
			// Only one value, push it!
			push(this, start);
			this.text += start_len;
			break;
		case 2:
			if(start > stop) {
				serr | "Error: next range out of order '" | this.text |"'";
				exit(2);
			}
			for(int i = start; i <= stop; i++) {
				push(this, i);
			}
			this.text += stop_len;
			break;
		default:
			serr | "Error reading next block: '" | this.text |"', returned" | ret;
			exit(2);
		}

		if(this.text[0] == '\0') break;
	}
	this.com = -1;
}

int main(int argc, char * argv[]) {
	if(argc != 2) {
		serr | "Usage:" | argv[0] | "range";
		return 1;
	}

	RangeParser rp = { argv[1] };

	for() {
		int i = next(rp);
		if(i < 0) break;
		sout | i | nonl;
	}
	sout | nl;
}