Mercurial Hosting > luan
view core/src/luan/impl/UnmExpr.java @ 404:d55e873e1f0d
metatables now only apply to tables
author | Franklin Schmidt <fschmidt@gmail.com> |
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date | Wed, 29 Apr 2015 07:04:40 -0600 |
parents | 3dcb0f9bee82 |
children | bbad2d06f728 |
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package luan.impl; import luan.Luan; import luan.LuanFunction; import luan.LuanException; import luan.LuanSource; import luan.LuanBit; import luan.LuanTable; // unary minus final class UnmExpr extends UnaryOpExpr { UnmExpr(LuanSource.Element se,Expr op) { super(se,op); } @Override public Object eval(LuanStateImpl luan) throws LuanException { Object o = op.eval(luan); Number n = Luan.toNumber(o); if( n != null ) return -n.doubleValue(); LuanBit bit = luan.bit(se); if( o instanceof LuanTable ) { LuanFunction fn = bit.getHandlerFunction("__unm",(LuanTable)o); if( fn != null ) { return Luan.first(bit.call(fn,"__unm",new Object[]{o})); } } throw bit.exception("attempt to perform arithmetic on a "+Luan.type(o)+" value"); } }