*/
public static CollectionExpression range( NumericExpression start, NumericExpression end, NumericExpression step )
{
if ( step == null )
{
return new Value( new FunctionExpression( "range", new Expressions( new Expression[]{start, end} ) ) );
}
else
{
return new Value( new FunctionExpression( "range", new Expressions( new Expression[]{start, end,
step} ) ) );
}
}