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There is a newer version: 1.0.11

package jscl.text;

import jscl.math.Generic;
import jscl.text.msg.Messages;

import javax.annotation.Nonnull;

/**
 * User: serso
 * Date: 10/27/11
 * Time: 2:44 PM
 */
class PlusOrMinusTerm implements Parser {

	public static final Parser parser = new PlusOrMinusTerm();

	private PlusOrMinusTerm() {
	}

	public Generic parse(@Nonnull Parameters p, Generic previousSumElement) throws ParseException {
		int pos0 = p.getPosition().intValue();

		ParserUtils.skipWhitespaces(p);

		boolean sign = false;
		if (p.getPosition().intValue() < p.getExpression().length() && (p.getExpression().charAt(p.getPosition().intValue()) == '+' || p.getExpression().charAt(p.getPosition().intValue()) == '-')) {
			sign = p.getExpression().charAt(p.getPosition().intValue()) == '-';
			p.getPosition().increment();
		} else {
			ParserUtils.throwParseException(p, pos0, Messages.msg_10, '+', '-');
		}

		final Generic result = ParserUtils.parseWithRollback(TermParser.parser, pos0, previousSumElement, p);

		return sign ? result.negate() : result;
	}

}