<story><title>Elm is Wrong</title><url>http://reasonablypolymorphic.com/blog/elm-is-wrong</url></story><parent_chain><item><author>Singletoned</author><text>&amp;gt; I&amp;#x27;m a Python programmer. I fully expect dict keys to be able to be arbitrary objects.&lt;p&gt;I&amp;#x27;m a Python programmer too, and I also fully expect dict keys to be able to be arbitary objects, and I get really frustrated with the fact that they can&amp;#x27;t be arbitary objects.  They have to be hashable objects, and the hash function refuses to hash certain objects that it has decided aren&amp;#x27;t allowed.</text></item><item><author>sametmax</author><text>I&amp;#x27;m not particularly interested in Elm, but basically this post is about one problem in the language. One. This doesn&amp;#x27;t make the language a pile of garbage as the author seems to let you think.&lt;p&gt;I&amp;#x27;m a Python programmer. I fully expect dict keys to be able to be arbitrary objects. But after coding a lot in JS, I realized I could live without it. It&amp;#x27;s nice, but it&amp;#x27;s not a show stopper if I don&amp;#x27;t have it.&lt;p&gt;Same goes here. Yes, typing is not as good as you wish it was, but Elm is a young language, give it time to evolve. In the meantime, what about the innovative things in it ?</text></item></parent_chain><comment><author>Erwin</author><text>Well, you cannot use a mutable object as a key without some help. What would you expect to happen if the object is modified after being inserted into the dictionary?&lt;p&gt;If you have a list or dictionary you want to use a key, you can convert it into a tuple which would make it immutable.&lt;p&gt;If you don&amp;#x27;t care about performance for larger collections you could just use a list instead of a dictionary, which does not require hashing. Changes to the original mutable object will also be reflected in your list.</text></comment>
<story><title>Elm is Wrong</title><url>http://reasonablypolymorphic.com/blog/elm-is-wrong</url></story><parent_chain><item><author>Singletoned</author><text>&amp;gt; I&amp;#x27;m a Python programmer. I fully expect dict keys to be able to be arbitrary objects.&lt;p&gt;I&amp;#x27;m a Python programmer too, and I also fully expect dict keys to be able to be arbitary objects, and I get really frustrated with the fact that they can&amp;#x27;t be arbitary objects.  They have to be hashable objects, and the hash function refuses to hash certain objects that it has decided aren&amp;#x27;t allowed.</text></item><item><author>sametmax</author><text>I&amp;#x27;m not particularly interested in Elm, but basically this post is about one problem in the language. One. This doesn&amp;#x27;t make the language a pile of garbage as the author seems to let you think.&lt;p&gt;I&amp;#x27;m a Python programmer. I fully expect dict keys to be able to be arbitrary objects. But after coding a lot in JS, I realized I could live without it. It&amp;#x27;s nice, but it&amp;#x27;s not a show stopper if I don&amp;#x27;t have it.&lt;p&gt;Same goes here. Yes, typing is not as good as you wish it was, but Elm is a young language, give it time to evolve. In the meantime, what about the innovative things in it ?</text></item></parent_chain><comment><author>ccapndave</author><text>&lt;a href=&quot;http:&amp;#x2F;&amp;#x2F;package.elm-lang.org&amp;#x2F;packages&amp;#x2F;eeue56&amp;#x2F;elm-all-dict&amp;#x2F;latest&quot; rel=&quot;nofollow&quot;&gt;http:&amp;#x2F;&amp;#x2F;package.elm-lang.org&amp;#x2F;packages&amp;#x2F;eeue56&amp;#x2F;elm-all-dict&amp;#x2F;lat...&lt;/a&gt;</text></comment>