Search inside the OCaml documentation

1. A Tour of OCaml

   Type Conversion and Type-Inference

   ison to other languages. Arguably, this saves more time than we lose by being more explicit. In OCaml you need to explicitly convert the integer to a floating point number using the float_of_int function: In the first example, + is intended to be used with integers, so it can't be used with the 2.5 float. In the second example, +. is intended to be used with floats, so it can't be used with th

   First Steps

2. A Tour of OCaml

   Pattern Matching, Cont'd

   mes, just as let does. In the third pattern, x designates the data inside the double-wrapped option. Pattern matching isn't limited to lists. Any kind of data can be inspected using it, except functions. Patterns are expressions that are compared to an inspected value. It could be performed using if … then … else … , but pattern matching is more convenient. Here is an example using the opti

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3. A Tour of OCaml

   Records

   Here, the pattern { age = x; _ } is typed with the most recently declared record type that has an age field of type int . The type int is inferred from the expression 13 <= x && x <= 19 . The function is_teenager will only work with the found record type, here person . When defining gerard , no type needs to be declared. The type checker will search for a record which has exactly three fiel

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4. Configuring Your Editor

   1) Hovering for Type Information

   This is a great feature that let's you see type information of any OCaml variable or function. All you have to do is place your cursor over the code and it will be displayed in the tooltip. VSCode Hovering

   Tooling

5. Configuring Your Editor

   Finer configuration

   OCaml-eglot can be finely configured, the project README gives several configuration paths to adapt perfectly to your workflow. You will also find there an exhaustive presentation of the different functions offered by the mode.

   Tooling

6. Configuring Your Editor

   Getting Type Information

   OCaml-eglot README provides a comprehensive overview of all the functions available in this mode! Emacs Type information Opening an OCaml file should launch an ocaml-lsp server, and you can convince yourself that it's working by using, for example, the ocaml-eglot-ty

   Tooling

7. Your First OCaml Program

   Installing and Using Modules From a Package

   efer to the Sexplib documentation for more information. Next, define a string containing a valid S-expression in bin/main.ml . Parse it into a S-expression with the Sexplib.Sexp.of_string function, and then convert it back into a string with Sexplib.Sexp.to_string and print it. To illustrate this, let's update our hello project to parse a string containing an S-expression and print

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8. Your First OCaml Program

   Using the Preprocessor to Generate Code

   le, and edit it to look like this: Let's assume we'd like hello to display its output as if it was a list of strings in UTop: ["hello"; "using"; "an"; "opam"; "library"] . To do that, we need a function turning a string list into a string , adding brackets, spaces, and commas. Instead of defining it ourselves, let's generate it automatically with a package. We'll use ppx_deriving . Here is how t

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