examples/purity-test.milch


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; utils

(let println! (\![x]
    (print! (fmt "{0}\n" [x]))))

; pure vs. impure demo

; this is a pure function
(let f (\[x] x))

(f 10) ; works

; this is an impure function
(let g! (\![x] (println! x)))

(g! "foo") ; works

; this is a pure function that tries to call an impure function
(let h (\[x] (g! x)))

(h "bar")
; error: cannot call impure function in pure context
;   when calling function g! at examples/purity-test.milch:19:15
;   in a function definition at examples/purity-test.milch:19:12
;   when calling function h at examples/purity-test.milch:21:1