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<p style="margin: 1.2em 0px ! important;">I tried this:</p>
<pre style="font-size: 0.85em; font-family: Consolas,Inconsolata,Courier,monospace;font-size: 1em; line-height: 1.2em;margin: 1.2em 0px;"><code style="font-size: 0.85em; font-family: Consolas,Inconsolata,Courier,monospace;margin: 0px 0.15em; padding: 0px 0.3em; white-space: pre-wrap; border: 1px solid rgb(234, 234, 234); background-color: rgb(248, 248, 248); border-radius: 3px; display: inline;white-space: pre; overflow: auto; border-radius: 3px; border: 1px solid rgb(204, 204, 204); padding: 0.5em 0.7em; display: block ! important;display: block; padding: 0.5em; color: rgb(51, 51, 51); background: none repeat scroll 0% 0% rgb(248, 248, 255);" class="hljs language-haskell"><span class="hljs-pragma">{-# LANGUAGE TypeFamilies #-}</span>
<span class="hljs-class">
<span class="hljs-keyword">class</span> <span class="hljs-type">C</span> x <span class="hljs-keyword">where</span></span>
<span class="hljs-typedef"><span class="hljs-keyword">type</span> <span class="hljs-type">A</span> x</span>
</code></pre>
<p style="margin: 1.2em 0px ! important;">It fails with this
error:</p>
<pre style="font-size: 0.85em; font-family: Consolas,Inconsolata,Courier,monospace;font-size: 1em; line-height: 1.2em;margin: 1.2em 0px;"><code style="font-size: 0.85em; font-family: Consolas,Inconsolata,Courier,monospace;margin: 0px 0.15em; padding: 0px 0.3em; white-space: pre-wrap; border: 1px solid rgb(234, 234, 234); background-color: rgb(248, 248, 248); border-radius: 3px; display: inline;white-space: pre; overflow: auto; border-radius: 3px; border: 1px solid rgb(204, 204, 204); padding: 0.5em 0.7em; display: block ! important;display: block; padding: 0.5em; color: rgb(51, 51, 51); background: none repeat scroll 0% 0% rgb(248, 248, 255);">Temp/jhc1.hs:4 - Error: parse error at "}"
</code></pre>
<p style="margin: 1.2em 0px ! important;">Standalone type families
don’t work either:</p>
<pre style="font-size: 0.85em; font-family: Consolas,Inconsolata,Courier,monospace;font-size: 1em; line-height: 1.2em;margin: 1.2em 0px;"><code style="font-size: 0.85em; font-family: Consolas,Inconsolata,Courier,monospace;margin: 0px 0.15em; padding: 0px 0.3em; white-space: pre-wrap; border: 1px solid rgb(234, 234, 234); background-color: rgb(248, 248, 248); border-radius: 3px; display: inline;white-space: pre; overflow: auto; border-radius: 3px; border: 1px solid rgb(204, 204, 204); padding: 0.5em 0.7em; display: block ! important;display: block; padding: 0.5em; color: rgb(51, 51, 51); background: none repeat scroll 0% 0% rgb(248, 248, 255);" class="hljs language-haskell"><span class="hljs-pragma">{-# LANGUAGE TypeFamilies #-}</span>
<span class="hljs-typedef"><span class="hljs-keyword">type</span> <span class="hljs-keyword">family</span> <span class="hljs-type">A</span> x</span>
</code></pre>
<pre style="font-size: 0.85em; font-family: Consolas,Inconsolata,Courier,monospace;font-size: 1em; line-height: 1.2em;margin: 1.2em 0px;"><code style="font-size: 0.85em; font-family: Consolas,Inconsolata,Courier,monospace;margin: 0px 0.15em; padding: 0px 0.3em; white-space: pre-wrap; border: 1px solid rgb(234, 234, 234); background-color: rgb(248, 248, 248); border-radius: 3px; display: inline;white-space: pre; overflow: auto; border-radius: 3px; border: 1px solid rgb(204, 204, 204); padding: 0.5em 0.7em; display: block ! important;display: block; padding: 0.5em; color: rgb(51, 51, 51); background: none repeat scroll 0% 0% rgb(248, 248, 255);">Temp/jhc1.hs:3 - Error: parse error at "family"
</code></pre>
<p style="margin: 1.2em 0px ! important;">Is there an example
somewhere that I missed while googling?</p>
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