η-Reduction / Expansion makes SATySFi confused

01-ng.satyg

let const a _ = a
let always-zero = const 0
let _ = always-zero (always-zero true) % Error!
%                   ^~~~~~~~~~~~~~~~~
%                     Type Error
%                     this expression has type
%                       int,
%                     but is expected of type
%                       bool.

01-ok.satyg

let const a _ = a
let always-zero x = const 0 x
let _ = always-zero (always-zero true)