Inspecting the code repository of a client, I found something like this:

var customer = new
{
    Id = default(int),
    Name = default(string)
};

var list = new int[0].Select(i => customer).ToList();

I confess that I needed some time to understand it. But, after some consideration, I figured out that what this code is doing is to create an empty strongly typed list of … an anonymous type.

Smart code. Yeah! But, please, don’t do that.

This Post Has 6 Comments

  1. Bruno

    It’s clear for me that’s it’s bad thing from a design view, but what’s about the performance ?

    1. elemarjr

      Allocations are not good for performance : array, enumerator (structure, but), closure,..

      1. elemarjr

        And… The “model” instance

  2. Aroldo Peixe

    Shit happens…

  3. Anderson

    Should we change anonymous by nested private class and new int[0].Select(…) by Enumerable.Repeate(…, 0) ?
    Is ToList() (or ToArray) itself a problem as I already have a IEnumerable after Select ? ToList helps while debugging, should I remove all unecessary of them?

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