OCaml's approach to semicolons is nice—they are clearly nothing more than sequence markers between side-effecting expressions. a ; b (* a THEN b *

OCaml's approach to semicolons is nice—they are clearly nothing more than sequence markers between side-effecting expressions. a ; b (* a THEN b *) a b (* a APPLIED TO b *) You also can basically just desugar them to let bindings a ; b == let _ = a in b a ; b ; c ; d e == let _ = a in let _ = b in let _ = c in d e Due to static typing it's vanishingly unlikely that a forgotten semicolon will properly check. let this = x ; y (* if x : 'a and y : 'b then this : 'b *) let this = x y (* if x : 'a -> 'b and y : 'a then this : 'b *) So forgetting a semicolon only check if `x` is an unapplied function of type `'a -> 'a` which the value you intended to completely ignore.