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POPlease explain in the simplest, most jargon-free English possible, the "universal property of fold"?
 

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  1. POPlease explain in the simplest, most jargon-free English possible, the "universal property of fold"?
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    <p>I am working through "Real World Haskell", which led to to a free PDF called <a href="http://www.google.com/url?sa=t&amp;source=web&amp;ct=res&amp;cd=1&amp;url=http%3A%2F%2Fwww.cs.nott.ac.uk%2F~gmh%2Ffold.pdf&amp;ei=G5gESt-OPNKLtgfMrIGbBw&amp;rct=j&amp;q=%22A+tutorial+on+the+universality+and+expressiveness+of+fold%22&amp;usg=AFQjCNG81_xijGu4ipQdCGBIxkR8z1Lj6w" rel="noreferrer">"A tutorial on the universality and expressiveness of fold"</a>. It makes the point that a "fold" is "universal". I am wrestling with his definition of "universal", and would like to hear the from those who have already invested time digesting it: <strong>Please explain in the simplest, most jargon-free English possible, the "universal property of fold"?</strong> What is this "universal property", and why is it important?</p> <p>Thanks.</p>
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    1. USGuy Coder
    1. USCharlie Flowers
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      1. POPlease explain in the simplest, most jargon-free English possible, the "universal property of fold"?
      1. USScott Weinstein
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      1. POPlease explain in the simplest, most jargon-free English possible, the "universal property of fold"?
      1. USmquander
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      1. POPlease explain in the simplest, most jargon-free English possible, the "universal property of fold"?
      1. USnlucaroni
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    1. CO4 years since I asked, and just tonight I came across an article talking about this. I don't know if it will fully answer my question, but it is definitely related. Search this url for "universal property": http://jeremykun.com/2013/04/16/categories-whats-the-point/
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      1. POPlease explain in the simplest, most jargon-free English possible, the "universal property of fold"?
      1. USCharlie Flowers
    2. COFunnily, four years ago I didn't know what a universal property was either. Now I'm writing that series of blog posts. What a coincidence that I ran across this while writing a more detailed post on universal properties. Should be done in the next week.
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      1. POPlease explain in the simplest, most jargon-free English possible, the "universal property of fold"?
      1. USJeremyKun
    3. CO@Bean, glad to hear it! I will be looking forward to reading it. Because though I am starting to have an inkling, I'm still a *long* way from being able to claim I deeply understand what a universal property is.
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      1. POPlease explain in the simplest, most jargon-free English possible, the "universal property of fold"?
      1. USCharlie Flowers
 

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