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Revision as of 09:54, 27 November 2011 by Dave4420 (talk | contribs) (§6.4 Other monoidal classes)

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Adding Exercises

I'd like to add a bunch of explicit, typographically distinguished exercises to the text. For example, the Haskell wikibook typesets exercises in a centered box. I don't know a lot about wiki markup -- does anyone have ideas on a good way to do this?

Byorgey 16:09, 26 November 2011 (UTC) If you look at the source, it doesn't seem too complicated to copy over - only calls 1 or 2 other templates an those may not be important. --Gwern 16:20, 26 November 2011 (UTC)

That works great, thanks! Byorgey 17:34, 26 November 2011 (UTC)

§6.4 Other monoidal classes

This section states that instances of Alternative/MonadPlus/ArrowPlus are sometimes the same as the Monoid instance, and sometimes different. It would be helpful (imo) if it was explained why this is: whether it would be better if instances of Alternative/MonadPlus/ArrowPlus were the same as the Monoid instance, and that sometimes they are not due to accidents of history; or whether sometimes these instances should be different, and giving guidance as to when those times are.

--Dave4420 17:16, 26 November 2011 (UTC)

Hmm, where does it say that? Byorgey 17:40, 26 November 2011 (UTC)

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simple example of a MonadPlus instance is [], which is exactly the same as the Monoid instance for []: the empty list represents failure, and list concatenation represents choice. In general, however, a MonadPlus instance for a type need not be the same as its

Monoid instance; Maybe is an example of such a type.
--Dave4420 09:54, 27 November 2011 (UTC)


I'm not entirely happy about the situation with citations. Although I like having inline links, a bunch of information is lost by just giving a link rather than a full bibliography entry. I plan to add more citations so just linking to the old .bib file is insufficient. What would be the best way to maintain the actual citation/bibliography info? Is it as easy as copying over some wikipedia citation templates? --Byorgey 18:46, 26 November 2011 (UTC)

<code> vs <hask> tags

I'd like to standardize on using <haskell> tags to surround code blocks, but <code> tags to surround inline code. My reasons:

  1. <hask> tags seem to break a lot of things (e.g. they cannot be used inside links, etc.)
  2. The formatting with <hask> tags is inconsistent: Monad and Applicative are different colors, &&& does not look right, etc. Even if the formatting were consistent it would still be distracting: having different sorts of things be different colors helps when reading a code block, because it gives you some visual structure. Having different-colored things in the middle of paragraphs, on the other hand, only serves to distract one's attention when trying to read.

Broken sidebar

Typeclassopedia#Further_reading_3 has a broken sidebar and I can't figure out how to fix it. --Dag 02:05, 27 November 2011 (UTC)

The problem was that the sidebar content contained an = symbol. See [1]. The solution is to either surround each = with double curly braces like {{=}}, or to prefix the content with 1= (like {{note|1=...}}) to treat it as a named rather than anonymous argument to the template. I've also had to watch out for this when typesetting exercises containing things like (>>=). --Byorgey 06:25, 27 November 2011 (UTC)