Arrow operator ->


I was reading a code and I came across the following:

r(x, δ, b) = [ δ[i] - norm(x - b[:,i]) for i in 1:length(δ) ]
J(x) = ForwardDiff.jacobian(x->r(x, δ, b), x)
xs, err = gauss_newton(x->r(x, δ, b), J, x0)

Could you please explain what the → indicates and provide any doc I could read to understand? I am quite new to this. Thanks for the help!

Thank you

It creates an anonymous function.


Thank you!

More generally if you need to know what syntax does the REPL help mode can be a good starting (and maybe end!) point:

help?> ->
search: ->

  x -> y

  Create an anonymous function mapping argument(s) x to the function body y.

  julia> f = x -> x^2 + 2x - 1
  #1 (generic function with 1 method)

  julia> f(2)

This and other symbols are defined here in the documentation.

1 Like

Thanks a lot!