I'm having trouble understanding the explanation of the meaning of the signature of runST at<div><div><div><div><br></div><div><a href="http://en.wikibooks.org/wiki/Haskell/Existentially_quantified_types">http://en.wikibooks.org/wiki/Haskell/Existentially_quantified_types</a><br>
</div><div><br></div><div>I could try to read the article a couple of times again, but are there any other good readings about these existentially quantified types and how the ST monad works? </div><div><br></div><div>I'm currently only using forall in combination with type classes, as in data MVC m v = forall c. Controller c => MVC m v c</div>
<div><br></div><div>However - as the article mentions - forall can also be used to constrain the scope of type variables, but I don't get it yet.</div><div><br></div><div>Thanks!<br></div><div><br></div><div><br></div>
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