49 lines
1.1 KiB
OCaml
49 lines
1.1 KiB
OCaml
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let m = [ ("dog", 1); ("chicken", 2); ("dog", 3); ("cat", 5) ]
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let rec lookup_all s m =
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match m with
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| [] -> []
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| (name,value)::ms ->
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let rest = lookup_all s ms
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in if s = name then value :: rest else rest
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(* find all by : (’a -> ’a ->bool) -> ’a ->
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’a list -> ’a list
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*)
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let streq s1 s2 = s1 = s2
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let check (s,i) s' = s = s'
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let rec find_all_by eq v l =
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match l with
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| [] -> []
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| x::xs -> if eq x v
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then x :: find_all_by eq v xs
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else find_all_by eq v xs
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let rec snds l =
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match l with
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| [] -> []
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| (f,s)::rest -> s :: snds rest
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let rec find_all_with f lst = match lst with
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| [] -> []
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| x::xs ->
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let rest = find_all_with f xs
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in if f x then x::rest else rest
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let find_all_by' eq e lst = find_all_with (fun x -> eq x e) lst
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(*
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drop_while even [2;4;6;8;9;4;2] ==> [9;4;2]
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drop_until even [1;3;5;2;4;6;8;9;4;2] ==> [2;4;6;8;9;4;2]
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*)
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(* flip: ('a -> 'b -> 'c) -> ('b -> ('a -> 'c)) *)
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let flip f x y = f y x
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(* (’b->’c)->(’a->’b)->(’a->’c) *)
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let compose f g x = f (g x)
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