Talk:Product type

Missing definition
It is not a good idea to to use the word that is being defined in its own definition. This article is a good example of a definition that does just that, and leaves the uninitiated no wiser. It would certainly be very nice if someone who does understand this issue to explain it in concrete terms. Thanks. FreeFlow99 (talk) 15:36, 31 March 2013 (UTC)


 * I agree with FreeFlow99: and above all it lacks any hint in what a product type is different from a trivial tuple. — Preceding unsigned comment added by 62.77.56.18 (talk) 09:03, 20 June 2013 (UTC)


 * Agreed. The industrious individual could do no harm by adding content taken from either the ncatlab page, or from the HoTT book. Both have a decent explanation of the idea. 99.153.64.179 (talk) 18:15, 26 June 2013 (UTC)


 * According to This C++ pattern-matching proposal, sum types correspond to C++'s  and product types correspond to  .  That's in keeping with the definition on the page now (an ordered tuple), and it makes the concept a lot easier for programmers who aren't programming theorists to comprehend.  I hesitate to add it, though, without a better reference.  --50.1.143.209 (talk) 19:12, 11 October 2016 (UTC)

Unclear paragraph.
"If there are only two component types, it can be called a "pair type". For example, if two component types A and B are the set of all possible values of that type"...

Which type? Do A and B somehow add up to all possible values of 'that' type, or does each represent all possible values of 'that' type separately? Or do A and B independently represent all possible values of two different types? - If it's the latter, there might be some expression available using the word 'each' which would express your intended meaning.

The text that I've quoted above is unclear, and it makes the whole paragraph unclear. Please fix this. Comiscuous (talk) 21:32, 30 May 2021 (UTC)