Poll: New name for mappend

I think a symmetric operator is best here, since mappend is associative. Look at (.), (<$>), (*) for prior art on symmetric operators being associative but not necessarily commutative.

There's a "unicode haskell" package around somewhere ISTR; I'd suggest they add ⊕ (\u2295) as the Unicode alias for the ASCII ++ used everywhere else.

Unicode is nice and can make things pretty when used well, but it should certainly not be the default. There are still too many people with poor Unicode support (either in fonts or keyboards) to make it work. That way lies APL.

I though Data.Sequence used ><, anyway?

I'll be happy as long it is not unicode. Most keyboards does not have unicode mapping so at least in the nearest future it will not be easy to enter.

I would be ok with ++ but I think there is a cultural issue with using more general types that dates back to the great monomorphization wave of 98, which makes it unlikely to be accepted. I would love to be proved wrong!

++ is ideal but it would break some of the existing code because of type inference issues and I think it would be a major gain if everyone got accustomed to inserting unicode symbols, so ⊕ (\u2295).

If going with unicode, I'd suggest U+2219 (and possibly U+2217,U+2218). These are bullet, asterisk, ring operators, respectively. &#x2219;

unfortunately, it doesn't show unicode chars