// File: Environment.cpp

#include "Environment.h"

using namespace std;

Environment::Environment() {
}


void Environment::insert(const string& n, int v) {
	bindings[n]=v;
}


int Environment::lookup(const string& n) const throw (VarException) {
	StringInt::const_iterator i;
	if((i=bindings.find(n)) != bindings.end())
		return (*i).second;
	else throw VarException("Variable " + n + " not in environment.");
}


bool Environment::isPresent(const string& n) const {
	return bindings.find(n) != bindings.end();
}


string Environment::toString() const {
	char buf[20];
	string s;
	int count=0,size=bindings.size();
	for(StringInt::const_iterator i=bindings.begin(); i!=bindings.end(); i++) {
		s += (*i).first + "=" + _itoa((*i).second,buf,10);
		if(++count!=size) 
			s += ", ";
	}
	return s;
}


Environment::~Environment() {
}