private Tree expressionPro(){
		Tree conditionalExpression = null, expression = null;
		
		if((conditionalExpression = conditionalExpressionPro()) != null){
			if((accept(Symbol.Id.PUNCTUATORS,"=")) != null){
				if((expression = expressionPro()) != null){
					return new AssignmentExpression(conditionalExpression, expression);
				}
				
				return null;
			}
			
			return conditionalExpression;
		}
		
		return null;
	}