ocaml - Expression of different type expected -


i have following code:

    type point  = { x : float; y : float; z : float }     type dpoint = { dx : float; dy : float; dz : float }     type physical_object = { position : point; velocity : dpoint }     let move p dp = {x = p.x + dp.x; y = p.y + dp.y; z = p.z + dp.z}

i getting error:

file "code.ml", line 4, characters 21-24: error: expression has type float expression expected of type          int

p.x highlighted

why this? not referencing record's fields correctly?

operator + has type int -> int -> int , applicable values of type int. use +. operator floats, (and *., /. correspondingly other operations).

ocaml doesn't have operator overloading (aka ad hoc polymorphism), doesn't play type inference. however, makes code more explicit, can considered benefit.


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