public static Expression <Hoisted <TIn, TOut> > Hoist(Expression <Func <TIn, TOut> > expr)
{
// rewrite Expression<Func<TIn, TOut>> as Expression<Hoisted<TIn, TOut>>
var visitor = new HoistingExpressionVisitor <TIn, TOut>();
var rewrittenBodyExpr = visitor.Visit(expr.Body);
var rewrittenLambdaExpr = Expression.Lambda <Hoisted <TIn, TOut> >(rewrittenBodyExpr, expr.Parameters[0], _hoistedConstantsParamExpr);
return(rewrittenLambdaExpr);
}
