Comment by ekipan

From the article:

    length = foldr (+) 0 . map (const 1)
    length2d = foldr (+) 0 . map length

    -- and the proposed syntax the author calls more readable:
    length = foldr((+), 0, $) . map(const(1), $)
    length2d = foldr((+), 0, $) . map(length, $)

But I don't understand. Why does the author think it's confusing to partially apply foldr and map but not (+), (.), const, and length? Applied consistently:

    length = (.)(foldr((+)($, $), 0, $), map(const(1, $), $), $)
    length2d = (.)(foldr((+)($, $), 0, $), map(length($), $), $)

And clearly no-one thinks this strawman is clearer. Further, it's impossible to make it 100% consistent: any function you write with polymorphic result could instantiate as a function needing more arguments. I think currying is the better default.