https://github.com/nao1215/stringx
stringx - Unicode-aware string utilities in OCaml
https://github.com/nao1215/stringx
algorithm levenshtein-distance ocaml string
Last synced: 3 months ago
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stringx - Unicode-aware string utilities in OCaml
- Host: GitHub
- URL: https://github.com/nao1215/stringx
- Owner: nao1215
- License: mit
- Created: 2025-06-27T03:19:06.000Z (3 months ago)
- Default Branch: main
- Last Pushed: 2025-07-02T13:59:20.000Z (3 months ago)
- Last Synced: 2025-07-17T03:54:52.911Z (3 months ago)
- Topics: algorithm, levenshtein-distance, ocaml, string
- Language: OCaml
- Homepage:
- Size: 775 KB
- Stars: 8
- Watchers: 0
- Forks: 0
- Open Issues: 1
-
Metadata Files:
- Readme: README.md
- Funding: .github/FUNDING.yml
- License: LICENSE
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# Unicode-aware string utilities in OCaml
**stringx** is a OCaml library that brings robust Unicode (UTF-8) support to your string processing tasks.
> [!NOTE]
> This project is inspired by [huandu/xstrings](https://github.com/huandu/xstrings).
>
> The goal is to bring string manipulation features found in other programming languages to OCaml. **This library is under active development.**
> Function proposals and contributions for new string utilities are very welcome! As I am new to OCaml, I welcome your feedback and suggestions π
With stringx, you get:
- Accurate edit distance (Levenshtein) calculations for any language or emoji
- Smart centering of strings, even with multibyte characters
- Flexible character counting and deletion using intuitive patterns, ranges, and negation
---
## β¨ Features
- **Unicode-first:** All functions are fully UTF-8 awareβworks perfectly with emoji, Japanese, Chinese, and more!
- **Flexible pattern matching:** Use character sets, ranges (e.g. `"a-z"` or `"γ-γ"`), and negation (`"^0-9"`) for powerful string operations.
- **No C bindings:** Pure OCaml, easy to install and portable.
- **Battle-tested:** Includes comprehensive tests for edge cases and malformed UTF-8.
---
## π§ API Overview
The latest API documentation is published at:
π [https://nao1215.github.io/stringx/stringx/Stringx/index.html](https://nao1215.github.io/stringx/stringx/Stringx/index.html)
```ocaml
(** Computes the Levenshtein distance between two UTF-8 strings. *)
val distance : s:string -> t:string -> int
(** Centers a string within a specified length, padding as needed. *)
val center : len:int -> pad:string -> string -> string
(** Counts Unicode characters in a string that match a given pattern. *)
val count : pattern:string -> string -> int
(** Deletes Unicode characters from a string that match a given pattern. *)
val delete : pattern:string -> string -> string
(** Returns the number of Unicode code points in a string. *)
val length : string -> int
(** Reverses a UTF-8 encoded string by Unicode code points. *)
val reverse : string -> string
(** Checks if a string contains a specific substring. *)
val contains : substr:string -> string -> bool
(** Checks if a string contains any Unicode code points from a given set. *)
val contains_any : chars:string -> string -> bool
(** Checks if a string starts with a given prefix. *)
val has_prefix : prefix:string -> string -> bool
(** Checks if a string ends with a given suffix. *)
val has_suffix : suffix:string -> string -> bool
(** Counts non-overlapping occurrences of a substring. *)
val count_substring : substr:string -> string -> int
(** Compares two strings for equality, ignoring case (ASCII only). *)
val equal_fold : other:string -> string -> bool
(** Splits a string into a list of words, using whitespace as a delimiter. *)
val fields : string -> string list
(** Splits a string using a custom delimiter function. *)
val fields_func : f:(Uchar.t -> bool) -> string -> string list
(** Finds the first index of a substring. *)
val index : substr:string -> string -> int
(** Repeats a string a specified number of times. *)
val repeat : count:int -> string -> string
(** Joins a list of strings into a single string with a separator. *)
val join : sep:string -> string list -> string
(** Removes leading and trailing characters from a string that are in a given set. *)
val trim : cutset:string -> string -> string
(** Removes leading and trailing characters from a string based on a predicate. *)
val trim_func : f:(Uchar.t -> bool) -> string -> string
(** Removes leading characters from a string that are in a given set. *)
val trim_left : cutset:string -> string -> string
(** Removes leading characters from a string based on a predicate. *)
val trim_left_func : f:(Uchar.t -> bool) -> string -> string
(** Removes trailing characters from a string that are in a given set. *)
val trim_right : cutset:string -> string -> string
(** Removes trailing characters from a string based on a predicate. *)
val trim_right_func : f:(Uchar.t -> bool) -> string -> string
(** Removes leading and trailing whitespace from a string. *)
val trim_space : string -> string
(** Removes a trailing suffix from a string. *)
val trim_suffix : suffix:string -> string -> string
(** Converts a string to lowercase. *)
val to_lower : string -> string
(** Converts a string to title case. *)
val to_title : string -> string
(** Converts a string to uppercase. *)
val to_upper : string -> string
(** Converts a string to camelCase. *)
val to_camel_case : string -> string
(** Converts a string to kebab-case. *)
val to_kebab_case : string -> string
(** Converts a string to PascalCase. *)
val to_pascal_case : string -> string
(** Converts a string to snake_case. *)
val to_snake_case : string -> string
(** Applies a function to each Unicode code point in a string. *)
val map : f:(Uchar.t -> Uchar.t) -> string -> string
(** Maps and filters Unicode code points in a string. *)
val filter_map : f:(Uchar.t -> Uchar.t option) -> string -> string
(** Iterates over the Unicode code points in a string. *)
val iter : f:(Uchar.t -> unit) -> string -> unit
(** Folds over the Unicode code points in a string. *)
val fold : f:('acc -> Uchar.t -> 'acc) -> init:'acc -> string -> 'acc
(** Expands tab characters to spaces. *)
val expand_tabs : tab_size:int -> string -> string
(** Converts the first Unicode code point of a string to lowercase. *)
val first_rune_to_lower : string -> string
(** Converts the first Unicode code point of a string to uppercase. *)
val first_rune_to_upper : string -> string
(** Inserts a string into another at a specified index. *)
val insert : src:string -> index:int -> string -> string
(** Partitions a string by the last occurrence of a separator. *)
val last_partition : sep:string -> string -> string * string * string
(** Left-justifies a string within a specified width. *)
val left_justify : width:int -> pad:string -> string -> string
(** Partitions a string by the first occurrence of a separator. *)
val partition : sep:string -> string -> string * string * string
(** Right-justifies a string within a specified width. *)
val right_justify : width:int -> pad:string -> string -> string
(** Returns the display width of a Unicode code point. *)
val rune_width : Uchar.t -> int
(** Replaces invalid UTF-8 sequences in a string. *)
val scrub : repl:string -> string -> string
(** Randomly shuffles the Unicode code points in a string. *)
val shuffle : string -> string
(** Shuffles a string using a provided random source. *)
val shuffle_source : rand:Random.State.t -> string -> string
(** Extracts a slice of a string by Unicode code point indices. *)
val slice : start:int -> end_:int -> string -> string
(** Removes consecutive repeated characters that match a pattern. *)
val squeeze : pattern:string -> string -> string
```
---
## π¦ Installation
Using [opam](https://opam.ocaml.org/):
```sh
opam pin add stringx https://github.com/nao1215/stringx.git
```
Once released:
```sh
opam install stringx
```
---
## π Build from Source
```sh
git clone https://github.com/nao1215/stringx.git
cd stringx
opam install . --deps-only -y
dune build
```
Run tests:
```sh
dune runtest
```
Generate documentation:
```sh
opam install odoc
dune build @doc
xdg-open _build/default/_doc/_html/index.html
```
---
## π§βπ» Contributing
1. Format your code with `ocamlformat`.
2. Make sure `dune runtest` passes.
3. Add tests and documentation for new features.
Pull requests and issues welcome:
π [https://github.com/nao1215/stringx/issues](https://github.com/nao1215/stringx/issues)
---
## π License
This project is licensed under the [MIT License](./LICENSE).