let converge2Into abc za yb z y = abc (za z) (yb y)
let converge3Into abcd za yb xc z y x = (converge2Into abcd za yb z y) (xc x)
let converge4Into abcde za yb xc wd z y x w = (converge3Into abcde za yb xc z y x) (wd w)
let converge5Into abcdef za yb xc wd ve z y x w v = (converge4Into abcdef za yb xc wd z y x w) (ve v)

let (<^) = (<<)
let (<^^) ab cda c d = ab (cda c d)
let (<^^^) ab cdea c d e = ab (cdea c d e)
let (<^^^^) ab cdefa c d e f = ab (cdefa c d e f)
let (<^^^^^) ab cdefga c d e f g = ab (cdefga c d e f g)

let (^>) = (>>)
let (^^>) cda ab = ab <^^ cda
let (^^^>) cdea ab = ab <^^^ cdea
let (^^^^>) cdefa ab = ab <^^^^ cdefa
let (^^^^^>) cdefga ab = ab <^^^^^ cdefga