Standard ML of New Jersey (32-bit) v110.99 [built: Thu Dec 24 11:01:10 2020]
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- map;
val it = fn : ('a -> 'b) -> 'a list -> 'b list
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- map (fn x => x*x) [1,2,3,4,5];
val it = [1,4,9,16,25] : int list
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- map (fn x => 2*x) [1,2,3,4,5];
val it = [2,4,6,8,10] : int list
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- map String.size ["cat", "dog", "dogs", "apple", "pears"];
[autoloading]
[library $SMLNJ-BASIS/basis.cm is stable]
[library $SMLNJ-BASIS/(basis.cm):basis-common.cm is stable]
[autoloading done]
val it = [3,3,4,5,5] : int list
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- map explode ["cat", "dog", "dogs", "apple", "pears"];
val it =
  [[#"c",#"a",#"t"],[#"d",#"o",#"g"],[#"d",#"o",#"g",#"s"],
   [#"a",#"p",#"p",#"l",#"e"],[#"p",#"e",#"a",#"r",#"s"]] : char list list
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- filter;
stdIn:15.1-15.7 Error: unbound variable or constructor: filter
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- fun filter h (x::xs) = xs; (* wrong *)
stdIn:23.5-23.26 Warning: match nonexhaustive
          (h,x :: xs) => ...

val filter = fn : 'a -> 'b list -> 'b list
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- fun filter h (x::xs) = if (h x) then x :: filter h xs else filter h xs;
stdIn:26.5-26.71 Warning: match nonexhaustive
          (h,x :: xs) => ...

val filter = fn : ('a -> bool) -> 'a list -> 'a list
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- fun filter h [] = []
=   | filter h (x::xs) = if (h x) then x :: filter h xs else filter h xs;
val filter = fn : ('a -> bool) -> 'a list -> 'a list
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- filter (fn x => x>=0) [2, ~2, 3, 4, ~5, ~5, ~8, 0, 1, ~2];
val it = [2,3,4,0,1] : int list
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- filter (fn x => x<=0) [2, ~2, 3, 4, ~5, ~5, ~8, 0, 1, ~2];
val it = [~2,~5,~5,~8,0,~2] : int list
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