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POC# Casting oddity
 

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  1. POC# Casting oddity
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    <p>I'm playing around with generics in a weird circumstance and I've come across a weird situation whose "solution" I don't expect to work. Here's the offending code...</p> <pre><code>static TournamentGame&lt;T, Y&gt; make16Game&lt;T, Y&gt;(int gameId, int seed1, int seed2, List&lt;Y&gt; teams) where T : TournamentTeam&lt;Y&gt; where Y : Team { /* * bunch of code removed for clarity */ // return that bad boy return new TournamentGame&lt;T, Y&gt;(gameId, (T)(new TournamentTeam&lt;Y&gt;(seed1, teams[seed1 - 1])), (T)(new TournamentTeam&lt;Y&gt;(seed2, teams[seed2 - 1]))); } </code></pre> <p>Looking at this, I don't see how the compiler allows this. My intuition is that I'll get a runtime error if I ever invoke this with a <code>T</code> other than <code>TournamentTeam</code>. If I don't put in the cast, I get a compile error. Is my intuition on this correct? What I'd LOVE to do is enforce a constraint that <code>T</code> must have a constructor that takes a <code>String</code> and a <code>Y</code> parameter, but that's another issue. I suppose I could also use reflection to get that constructor for <code>T</code>, but where's the fun in that?</p> <p>Anyway, thoughts?</p> <p>EDIT The <code>TournamentGame</code> looks like the following:</p> <pre><code>public class TournamentGame&lt;T, Y&gt; : Game&lt;T&gt; where T : TournamentTeam&lt;Y&gt; where Y : Team { public TournamentGame(int id, T t1, T t2, Region&lt;T, Y&gt; region = null) : base(id, t1, t2) { // do your thang } } public class Game&lt;T&gt; where T : Team { private T mTeam1 = null; private Game(int id) { // do your thang } public Game(int id, T t1, T t2) : this(id) { // do your thang } public T Team1 { get { // do your thang } } } </code></pre> <p>Sorry for leaving that out.</p>
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    1. COPerhaps I am mistaken, but I see nothing generic in this method, just a really awkward way of using regular types.\
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      1. POC# Casting oddity
      1. USRitch Melton
    2. COwell, much of the reason for my using generics is hidden from this code example because the generics come in to play in the object types being used, not in this specific code. This function is a helper function for another static function that does require generics. I'm more asking about the cast in the return statement, though, and if that is a good or bad idea.
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      1. POC# Casting oddity
      1. USaaronburro
    3. COYou are correct, though. this question has nothing to do with generics, and I realized that before I hit the submit button and actually changed the title, but forgot to remove the generics tag. Removing that tag now.
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      1. POC# Casting oddity
      1. USaaronburro
 

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