public static int indexer(char x)throws IllegalLineException{
		//takes in a char and returns int to be used for indexing with Expression Checker's dictionary
		//throws IllegalLineException when the char is not of expected type
		//the final return of 100 is never reached.
		switch(x){
			case '|':case'&': return 0;
			case '(': return 1;
			case ')': return 2;
			case '~': return 3;
			case '=': return 5;
			case '>': return 6;
			default: if(!Character.isLetter(x)){
						throw new IllegalLineException("***Invalid Expression: "+x);
					}else{
						return 4;
					}
		}
	}