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Ocaml string histogram

I'm trying to do an Histogram from String in OCaml.I'm at this state, editing a little this: create a histogram OCaml to use a String input.How can I see the content of charFreqs, or does it...

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how to translate `if b < a` condition to match pattern?

Like the if .. then in code# let rec range2 a b accum = if b < a then accum else range2 a (b - 1) (b :: accum);;how to write this b < a as a pattern in match .. with ? sth likelet rec range2 a b...

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Solving OCaml Problems

Define a function sign which given an integer returns 1 if it is positive, -1 if it is negative and 0 if it is zero.my solutionssolution 1let sign i = if i!=0 then (if i<0 then -1 else 1) else...

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Ocaml parser for applying a function

I have a file, parser.mly, which has the following%{open Ast%}(* Ast holds the abstract syntax tree type definitions. *)%token EOF%token OR%left OR%start <Ast.prog> prog%% prog: | e = expr; EOF...

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How can I open List without importing the type List.t?

I'm using OCaml 5.3.0.I like to write open List at the top of my source files, since I use list functions so frequently that I don't want to have to prefix them as e.g. List.length or even L.length....

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How to debug OCaml dune test program?

Let's say I:dune init proj foobarcd foobarThen modify test/test_foobar.ml to be:let () = print_endline "First"let () = print_endline "Second"let () = print_endline "Third"I can execute the program with...

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Why does `let f : int -> int list -> int list = (::);;` fail?

I would think that OCaml would read the following as an instance of partial application, and store the function as f. However, the compiler complains that the function is applied to too few arguments....

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let in and the use of ; vs ;;

I have this chunk of code below. I'm a bit confused as to how the let in syntax should work. I was under the assumption that the let in let you use that variable in the scope of in. Although, I don't...

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How to print a list of lists

I'm trying to print a specific list, but it doesn't worklet rec listes_paires l = match l with | [] -> [] | x :: r -> if List.length x mod 2 = 0 then (x :: (listes_paires r)) else ((x @ x) ::...

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Base won't load in utop

So basically I am trying to follow these instructions https://dev.realworldocaml.org/install.htmlI followed them literally. I have a working utop. I have a working VS Code environment. I can run code...

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OCaml Option get

I'm new to OCaml, I'm trying to understand how you're supposed to get the value from an 'a option. According to the doc at http://ocaml-lib.sourceforge.net/doc/Option.html, there is a get function of...

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Time complexity of :: and @ (OCaml)

I was reading this and was wondering if :: is always more efficient than @ or if only in that particular implementation of revlet rec rev = function | [] -> [] | h::t -> rev t @ [h]let rev l =...

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Formatting numbers with thousand separators

Is there anything in the standard library or in Core that I can use to format integers with thousand separators?

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How to turn a set of sets to list

So I have two modules, for ex.module A = Set.Make (struct type t = ... let compare = Stdlib.compareend)module B = .... (virtually the same thing)Now the question, if I have n amount of elements of type...

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OCaml function parameter pattern matching for strings

I tried to pass a string in to get a reversed string. Why can't I do this:let rec reverse x = match x with | "" -> "" | e ^ s -> (reverse s) ^ e;;The compiler says it's a syntax error. Can't I...

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find longest repeating sequence in list

If I have a List like this:[i;i;i;a;b;b;a;i;i;c] (*the longest repeating sequence would be [i;i]*)[i;i;i;i] (*here the max_pattern would be [i;i] (has to repeat, no overlapping*)[t;f;f;t] (*here it...

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Reading integers from file OCaml

I have to read integers from a "file.txt" in OCaml and store them in a list. I have tried to read with stdlib but it does not work. Also I cannot understand how scanf works for files. If someone could...

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How can I quickly split an utf8 string into chars in OCaml?

I'm handling a string with special characters and I want to split it into Unicode characters, but apparently OCaml strings are encoded in utf-8 while OCaml chars are 1-byte values, and it appears that...

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