[Haskell-cafe] commending "Design concepts in programming languages"

Daniel Fischer daniel.is.fischer at web.de
Fri May 8 08:31:09 EDT 2009

Am Freitag 08 Mai 2009 13:23:09 schrieb Wolfgang Jeltsch:
> Am Donnerstag, 7. Mai 2009 14:42 schrieb Daniel Fischer:
> > Of course, if centuries ago people had decided to write the argument
> > before the function, composition would've been defined the other way
> > round. They haven't.
> Algebraists used to write x f instead of f(x) at least in the 1980s.

I think that should read *some* algebraists...
Though I had no contact with algebraists in the 1980s, if that practice had been 
ubiquitous among them, I would have expected it to show up in the textbooks. I've never 
seen it in an algebra book, nor was it used in any algebra lecture I attended in the 
1990s, so I doubt it was very widespread.
Don't get me wrong, that notation does make sense and has some advantages over the 
conventional one, I wouldn't oppose a change, though it would take some time to get used 
to it. All I'm saying is that the overwhelming majority of mathematicians doesn't use it.

> I think, also category theorists often wrote (write?) composition with the
> first morphism on the left, i.e., “the other way round”.

Yeah, I heard that, too. It's a field where the advantages of postfix notation show 
clearly and a young one, so for them it was relatively easy to switch.
You'd have a hard time persuading the statisticians and analysts, though.

> Best wishes,
> Wolfgang


More information about the Haskell-Cafe mailing list