view src/luan/interp/LeExpr.java @ 48:64ecb7a3aad7

rename Lua to Luan git-svn-id: https://luan-java.googlecode.com/svn/trunk@49 21e917c8-12df-6dd8-5cb6-c86387c605b9
author fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
date Fri, 28 Dec 2012 03:29:12 +0000
parents a443637829c1
children 8ede219cd111
line wrap: on
line source

package luan.interp;

import luan.Luan;
import luan.LuanFunction;
import luan.LuanException;
import luan.LuanSource;


final class LeExpr extends BinaryOpExpr {

	LeExpr(LuanSource.Element se,Expr op1,Expr op2) {
		super(se,op1,op2);
	}

	@Override public Object eval(LuanStateImpl lua) throws LuanException {
		Object o1 = op1.eval(lua);
		Object o2 = op2.eval(lua);
		if( o1 instanceof Number && o2 instanceof Number ) {
			Number n1 = (Number)o1;
			Number n2 = (Number)o2;
			return n1.doubleValue() <= n2.doubleValue();
		}
		if( o1 instanceof String && o2 instanceof String ) {
			String s1 = (String)o1;
			String s2 = (String)o2;
			return s1.compareTo(s2) <= 0;
		}
		LuanFunction fn = lua.getBinHandler(se,"__le",o1,o2);
		if( fn != null )
			return Luan.toBoolean( Luan.first(lua.call(fn,se,"__le",o1,o2)) );
		fn = lua.getBinHandler(se,"__lt",o1,o2);
		if( fn != null )
			return !Luan.toBoolean( Luan.first(lua.call(fn,se,"__lt",o2,o1)) );
		throw new LuanException( lua, se, "attempt to compare " + Luan.type(o1) + " with " + Luan.type(o2) );
	}
}