/*
 * This file contains utilities for the recursive descent parser.
 */
#ifndef _util_h_
#define _util_h_

#include <string>
using namespace std;

/* Print some spaces to a stream.   This class and the operator function
   allows stuff like:
       s << spaces(5) << "more stuff";
*/
class spaces {
public:
	spaces(int nsp): m_nsp(nsp) { }
private:
	int m_nsp;
	friend ostream &operator <<(ostream &strm, const spaces &);
};
inline ostream &operator <<(ostream &st, const spaces &sp)
{
	for(int n = sp.m_nsp; n--; ) st << " ";
	return st;
}


/* Abstract base class for stuff used by the parser. */
class ParserObject {
protected:
	// Print the object with the indicated indent amount.
	// Each object must implement this.
	virtual void pr(ostream &s, int indent) const = 0;
public:
	ostream & pro(ostream &s, int indent) const {
		pr(s,indent);
		return s;
	}
	
	// Print the object through the abstract printing method.
	void print(ostream &s) const {
		pr(s, 0);
	}
};

inline ostream &operator <<(ostream &st, const ParserObject &po)
{
	po.print(st);
	return st;
}

#endif