Melody is a language that compiles to ECMAScript regular expressions, while aiming to be more readable and maintainable.
## Examples
Note: these are for the currently supported syntax and may change
### Batman Theme try in playground
```rust
16 of "na";
2 of match {
;
"batman";
}
// 🦇🦸♂️
```
Turns into
```regex
(?:na){16}(?: batman){2}
```
### Twitter Hashtag try in playground
```rust
"#";
some of ;
// #melody
```
Turns into
```regex
#\w+
```
### Introductory Courses try in playground
```rust
some of ;
;
"1";
2 of ;
// classname 1xx
```
Turns into
```regex
[a-zA-Z]+ 1\d{2}
```
### Indented Code (2 spaces) try in playground
```rust
some of match {
2 of ;
}
some of ;
";";
// let value = 5;
```
Turns into
```regex
(?: {2})+.+;
```
### Semantic Versions try in playground
```rust
;
option of "v";
capture major {
some of ;
}
".";
capture minor {
some of ;
}
".";
capture patch {
some of ;
}
;
// v1.0.0
```
Turns into
```regex
^v?(?\d+)\.(?\d+)\.(?\d+)$
```
## Playground
You can try Melody in your browser using the [playground](https://melody-playground.vercel.app/)
## Book
Read the book [here](https://yoav-lavi.github.io/melody/book/)
## Install
### Cargo
```sh
cargo install melody_cli
```
### From Source
```sh
git clone https://github.com/yoav-lavi/melody.git
cd melody
cargo install --path crates/melody_cli
```
### Binary
- macOS binaries (`aarch64` and `x86_64`) can be downloaded from the [release page](https://github.com/yoav-lavi/melody/releases)
### Community
- [Brew](https://formulae.brew.sh/formula/melody) (macOS and Linux)
Installation instructions
```sh
brew install melody
```
Installation instructions
1. Installation with an AUR helper, for instance using `paru`:
```bash
paru -Syu melody
```
2. Install manually with `makepkg`:
```bash
git clone https://aur.archlinux.org/melody.git
cd melody
makepkg -si
```
Installation instructions
1. Declarative installation using `/etc/nixos/configuration.nix`:
```nix
{ pkgs, ... }:
{
environment.systemPackages = with pkgs; [
melody
];
}
```
2. Imperative installation using `nix-env`:
```sh
nix-env -iA nixos.melody
```
\`...\` - added directly to the output without any escaping
### Groups
- `capture` - used to open a `capture` or named `capture` block. capture patterns are later available in the list of matches (either positional or named). equivalent to regex `(...)`
- `match` - used to open a `match` block, matches the contents without capturing. equivalent to regex `(?:...)`
- `either` - used to open an `either` block, matches one of the statements within the block. equivalent to regex `(?:...|...)`
### Assertions
- `ahead` - used to open an `ahead` block. equivalent to regex `(?=...)`. use after an expression
- `behind` - used to open an `behind` block. equivalent to regex `(?<=...)`. use before an expression
Assertions can be preceeded by `not` to create a negative assertion (equivalent to regex `(?!...)`, `(?` | `\p{...}` | 🐣 |
| `not <...::...>` | `\P{...}` | 🐣 |
| file watcher | | ❌ |
| multiline groups in REPL | | ❌ |
| `flags: global, multiline, ...` | `/.../gm...` | ❔ |
| (?) | `\#` | ❔ |
| (?) | `\k` | ❔ |
| (?) | `\uYYYY` | ❔ |
| (?) | `\xYY` | ❔ |
| (?) | `\ddd` | ❔ |
| (?) | `\cY` | ❔ |
| (?) | `$1` | ❔ |
| (?) | $\` | ❔ |
| (?) | `$&` | ❔ |
| (?) | `x20` | ❔ |
| (?) | `x{06fa}` | ❔ |
| `any of "a", "b", "c"` \* | `[abc]` | ❓ |
| multiple ranges \* | `[a-zA-Z0-9]` | ❓ |
| regex optimization | | ❓ |
| standard library / patterns | | ❓ |
| reverse compiler | | ❓ |
\* these are expressable in the current syntax using other methods