OCaml Cookbook Recipes

The OCaml Cookbook is a place where OCaml developers share how to solve common tasks using packages from the ecosystem.

A task is something that needs to be done inside a project. A recipe is a code sample and explanations on how to perform a task using a combination of open source libraries. Some tasks can be performed using different combination of libraries, each is a different recipe. Tasks don't describe how to use the standard library or language features.

OCaml developers are warmly invited to contribute categories, tasks, and recipes. See the Cookbook section of the CONTRIBUTING.md file in our GitHub repo.

The OCaml guides are recommend reading, for instance recipes handle errors as described in the Error Handling guide.

Command Line

Task

Opam Packages Used

Parse Command Line Arguments

This task has no recipes yet, maybe you want to contribute a recipe!

Using the ANSI Terminal

This task has no recipes yet, maybe you want to contribute a recipe!

Compilation & Linking

Task

Opam Packages Used

Compile and Link to a Bundled C Library

This task has no recipes yet, maybe you want to contribute a recipe!

Generate OCaml Bindings for a C Library

This task has no recipes yet, maybe you want to contribute a recipe!

Compression

Task

Opam Packages Used

Decompress a Single File Compressed With GZIP using camlzip

camlzip

Compress a Single File with GZIP using camlzip

camlzip

Decompress a ZIP Archive Containing Multiple Files using camlzip

camlzip

Create a ZIP Archive Containing Multiple Files using camlzip

camlzip

Decompressing a Tarball

This task has no recipes yet, maybe you want to contribute a recipe!

Compress a Directory Into a Tarball

This task has no recipes yet, maybe you want to contribute a recipe!

Concurrency & Parallelism

Parallelism & Multi-Threading

Task

Opam Packages Used

Spawn a Thread and Receive a Response

This task has no recipes yet, maybe you want to contribute a recipe!

Pass Data Between Parallel Threads

This task has no recipes yet, maybe you want to contribute a recipe!

Single-Threaded Concurrency

Task

Opam Packages Used

Create and Await Promises using lwt

lwt

Timeout Reading From Stdin With Promises using async

async

lwt

Cryptography

Task

Opam Packages Used

Calculate the SHA-256 Digest of a File using cryptokit

Sign and Verify a Message With an HMAC Digest using cryptokit

Salt and Hash a Password With Argon2 using argon2

argon2

Salt and Hash a Password With PBKDF2

This task has no recipes yet, maybe you want to contribute a recipe!

Data Structures & Algorithms

Hash Tables

Task

Opam Packages Used

Use a Hash Table With Given Key and Value Types using the Standard Library

-

Sorting

Task

Opam Packages Used

Sorting Lists and Arrays using the Standard Library

-

Database

PostgreSQL

Task

Opam Packages Used

PostgreSQL CREATE, INSERT, SELECT

This task has no recipes yet, maybe you want to contribute a recipe!

PostgreSQL Aggregate Query

This task has no recipes yet, maybe you want to contribute a recipe!

PostgreSQL Full Text Search

This task has no recipes yet, maybe you want to contribute a recipe!

SQLite

Task

Opam Packages Used

SQLite CREATE, INSERT, SELECT using ppx_rapper_lwt

ppx_rapper_lwt ppx_rapper caqti-driver-sqlite3 caqti-lwt lwt

SQLite Full Text Search

This task has no recipes yet, maybe you want to contribute a recipe!

Data Formats

XML

Task

Opam Packages Used

Parse XML using ezxmlm

ezxmlm

Generate XML using ezxmlm

ezxmlm

YAML

Task

Opam Packages Used

Serialise YAML Data

This task has no recipes yet, maybe you want to contribute a recipe!

Deserialise YAML Data using hl_yaml

hl_yaml ppx_deriving_yojson

yaml ppx_deriving_yaml

Deserialise and Post-Process YAML Data using hl_yaml

hl_yaml ppx_deriving_yojson

yaml ppx_deriving_yaml

JSON

Task

Opam Packages Used

Serialise JSON Data using ppx_yojson_conv

ppx_yojson_conv yojson

Deserialise JSON Data using ppx_yojson_conv

ppx_yojson_conv yojson

CSV

Task

Opam Packages Used

Read Tuples / Records from CSV using csv

csv

Serialise Tuples / Records to CSV

This task has no recipes yet, maybe you want to contribute a recipe!

Date and Time

Task

Opam Packages Used

Get Today's Date using the Standard Library

-

Measure Elapsed Time

This task has no recipes yet, maybe you want to contribute a recipe!

Convert a Local Time to Another Time Zone

This task has no recipes yet, maybe you want to contribute a recipe!

Convert Between Date and Unix Timestamp

This task has no recipes yet, maybe you want to contribute a recipe!

Display Formatted Date and Time using the Standard Library

-

Parse Date and Time from String

This task has no recipes yet, maybe you want to contribute a recipe!

Debugging

Task

Opam Packages Used

Debug Print a Value using ppx_deriving

Log a Debug / Error Message to Stdout / Stderr

This task has no recipes yet, maybe you want to contribute a recipe!

Log to the Unix Syslog

This task has no recipes yet, maybe you want to contribute a recipe!

Encoding

Task

Opam Packages Used

URL- / Percent-Encode a String

This task has no recipes yet, maybe you want to contribute a recipe!

Encode a String as application/x-www-form-urlencoded

This task has no recipes yet, maybe you want to contribute a recipe!

Encode and Decode Bytestrings From Hex-Strings using hex

hex cstruct

Encode and Decode Base64

This task has no recipes yet, maybe you want to contribute a recipe!

Read and Write Integers in Little-Endian Byte Order

This task has no recipes yet, maybe you want to contribute a recipe!

File System

Task

Opam Packages Used

Read and Write from a Text File using the Standard Library

-

Basic File and Directory Operations using the Standard Library

-

This task has no recipes yet, maybe you want to contribute a recipe!

Change File Permissions

This task has no recipes yet, maybe you want to contribute a recipe!

This task has no recipes yet, maybe you want to contribute a recipe!

Find Files Matching a Pattern

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Random Values

Task

Opam Packages Used

Generate Random `int`, `float`, and `char` using mirage-crypto-rng

mirage-crypto-rng cstruct randomconv

Mathematics

Geographical Calculations

Task

Opam Packages Used

Calculate Geodistance Between Two Points using the Standard Library

-

Vector & Matrix Operations

Task

Opam Packages Used

Normalise a Vector using owl

owl

using the Standard Library

-

Matrix Addition and Multiplication using owl

owl

Invert a Matrix using owl

owl

Nearest-Neighbour Search

This task has no recipes yet, maybe you want to contribute a recipe!

Networking

Task

Opam Packages Used

TCP Client using lwt

lwt

TCP Server using lwt

lwt

Operating System

Task

Opam Packages Used

Run an External Command and Process Stdout using feather

feather

shexp

using the Standard Library

-

Run Piped External Commands using feather

feather

shexp

Read an Environment Variable using the Standard Library

-

Graphical User Interfaces

There's nothing in this category yet.

Text Processing

Regular Expressions

Task

Opam Packages Used

Validate an Email Address using re

re

Extract Phone Numbers from Text

This task has no recipes yet, maybe you want to contribute a recipe!

Replace All Occurrences of a Text Pattern With Another Pattern

This task has no recipes yet, maybe you want to contribute a recipe!

Match on Groups in Regular Expressions using ppx_regexp

using the Standard Library

-

Unicode / UTF-8

Task

Opam Packages Used

Collect Unicode Graphemes

This task has no recipes yet, maybe you want to contribute a recipe!

UTF-8 Text Processing using camomile

Web Programming

URL and URI Processing

Task

Opam Packages Used

Parse a URI from String and Access Individual Parts using uri

uri

Encode a URI to String using uri

uri

Media Types (MIME)

Task

Opam Packages Used

Get MIME Type From String

This task has no recipes yet, maybe you want to contribute a recipe!

Get MIME Type From Filename

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Parse MIME Type of an HTTP Response

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Running a Web Server

Task

Opam Packages Used

Start a Web Server With a 'Hello World' Endpoint using cohttp-lwt-unix

cohttp-lwt-unix lwt

dream

Start a Web Server That Serves an HTML Template

This task has no recipes yet, maybe you want to contribute a recipe!

Use Basic Authentication to Secure a Route

This task has no recipes yet, maybe you want to contribute a recipe!

Dealing with HTML

Task

Opam Packages Used

Render an HTML Template

This task has no recipes yet, maybe you want to contribute a recipe!

Extract All Links From an HTML String using lambdasoup

HTTP Clients

Task

Opam Packages Used

Make a HTTP GET Request using cohttp-lwt-unix

cohttp-lwt-unix cohttp lwt

Make a HTTP GET Request With Basic Authentication

This task has no recipes yet, maybe you want to contribute a recipe!

Download a File to a Temporary Directory

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Make a Partial Download With HTTP Range Header

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Make an HTTP POST/PATCH Request with Bearer Token Authentication using cohttp

cohttp cohttp-lwt-unix lwt lwt_ppx tls-lwt