Standard ML of New Jersey (32-bit) v110.99 [built: Thu Dec 24 11:01:10 2020]
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- fun f x h = h x;
val f = fn : 'a -> ('a -> 'b) -> 'b
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- f 5 (fn x => x*x);
val it = 25 : int
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- f 7 (fn x => x*x);
val it = 49 : int
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- f 7 (fn x => x*x*x);
val it = 343 : int
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- f "cat" (fn s => s ^ s);
val it = "catcat" : string
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- f 5 (fn x => 1.0 + real x);
val it = 6.0 : real
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- f 5.0 (fn x => 1.0 + real x);
stdIn:13.1-13.29 Error: operator and operand do not agree [tycon mismatch]
  operator domain: real -> 'Z
  operand:         int -> real
  in expression:
    (f 5.0) (fn x => 1.0 + real x)
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- fun f g h x = g (h x);
val f = fn : ('a -> 'b) -> ('c -> 'a) -> 'c -> 'b
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- f (fn x => x*x) (fn x => 2 + x) 3;
val it = 25 : int
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- f (fn s => String.size s) (fn s => s ^ s) "cat";
[autoloading]
[library $SMLNJ-BASIS/basis.cm is stable]
[library $SMLNJ-BASIS/(basis.cm):basis-common.cm is stable]
[autoloading done]
val it = 6 : int
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- f (fn s => String.size s) (fn s => s ^ s) "cats";
val it = 8 : int
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