package com.creativewidgetworks.goldparser.simple2.rulehandlers;
import com.creativewidgetworks.goldparser.engine.ParserException;
import com.creativewidgetworks.goldparser.engine.Reduction;
import com.creativewidgetworks.goldparser.parser.GOLDParser;
import com.creativewidgetworks.goldparser.parser.ProcessRule;
import com.creativewidgetworks.goldparser.simple2.Simple2;
@ProcessRule(rule="<Statement> ::= while <Expression> do <Statements> end")
/**
* Rule handler for the while loop rule.
*
* @author Ralph Iden (http://www.creativewidgetworks.com)
* @version 5.0.0
*/
public class WhileLoop extends Reduction {
private Reduction conditional;
private Reduction statements;
public WhileLoop(GOLDParser parser) {
Reduction reduction = parser.getCurrentReduction();
if (reduction != null) {
if (reduction.size() == 5) {
conditional = reduction.get(1).asReduction();
statements = reduction.get(3).asReduction();
} else {
parser.raiseParserException(Simple2.formatMessage("error.param_count", "5", String.valueOf(reduction.size())));
}
} else {
parser.raiseParserException(Simple2.formatMessage("error.no_reduction"));
}
}
@Override
public void execute() throws ParserException {
conditional.execute();
while (conditional.getValue().asBool()) {
statements.execute();
conditional.execute();
}
}
}