<div dir="ltr">Hi Brandon,<br><div><div class="gmail_extra"><br><div class="gmail_quote">On Fri, May 31, 2013 at 8:01 PM, Brandon Allbery <span dir="ltr"><<a href="mailto:allbery.b@gmail.com" target="_blank">allbery.b@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr">On Fri, May 31, 2013 at 6:16 AM, mukesh tiwari <span dir="ltr"><<a href="mailto:mukeshtiwari.iiitm@gmail.com" target="_blank">mukeshtiwari.iiitm@gmail.com</a>></span> wrote:<br>
<div class="gmail_extra">
<div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div><div>Data.List can be abstracted using Foldable and Traversable but unfortunately I could not find the functions corresponding to head, take.<br>
</div></div></div></blockquote><div><br></div><div>Those are, again, more general than you want. What is the `head` of a HashMap? (Consider that an implementation may choose to randomize the hash function to avoid hash collision attacks.) Foldable and Traversable express the concept of a collection which has no meaningful concept of an element's relative position within the collection. ListLike adds the concept of position, thereby admitting an indexing operation (and, by extension, `head` which is index 0).</div>
</div></div></div></blockquote><div><br>Thanks for explanation. Precisely a tree was in the mind so there is no concept of head or take. Data.Foldable.toList could be used to convert the foldable structure to list but again it's not useful because Giacomo wants to abstract the List. <br>
<br></div><div>-Mukesh <br></div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">
<span class=""><font color="#888888">
<div><br></div></font></span></div><span class=""><font color="#888888">-- <br><div dir="ltr"><div>brandon s allbery kf8nh sine nomine associates</div><div><a href="mailto:allbery.b@gmail.com" target="_blank">allbery.b@gmail.com</a> <a href="mailto:ballbery@sinenomine.net" target="_blank">ballbery@sinenomine.net</a></div>
<div>unix, openafs, kerberos, infrastructure, xmonad <a href="http://sinenomine.net" target="_blank">http://sinenomine.net</a></div></div>
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