OOLANG is an esoteric stack-based programming language where all instructions/commands are differnet unicode O characters
We have a custom Web IDE at https://oolang.tech, for experimenting in the browser.
You can also install OOLANG on your system with Cargo:
rust
cargo install oolang
OOLANG files end in .oo, and consist of a number of commands specified each by a single unicode glyph. Any other character is ignored. Comments are supported using the # character, which comments out up to the end of the line.
oorun file.oo will execute your OOLANG program, reading from stdin and outputting to stdout.
OOLANG emulates a stack machine, not dissimilar to how the JVM or Python's bytecode interpreter works.
The virtual machine consists of a stack of bytes, and 256 bytes of addressable memory. A valid OOLANG program may consist of any combination of the the following 10 commands:
| Command | Unicode Character Name | Command Name | Description |
| ------- | -------------------------------------------- | ------------ | ------------------------------------------------------------------------------------------- |
| O | Latin Capital Letter O | PUSH | Push the value 1 onto the top of the stack |
| 0 | Digit Zero | POP | Pop the value from the top of the stack, discarding it |
| วพ | Latin Capital Letter O with Stroke and Acute | INC | Pop the top stack value, increment it, push the result |
| แซ | Cherokee Letter Wi | DEC | Pop the top stack value, decrement it, push the result |
| โญ | Heavy Large Circle | ADD | Pop the top two stack values, add them, push the result |
| ๐ | Gothic Letter Othal | JNZ | Jump to the address at the top of the stack, if the 2nd-top value is non-zero |
| ๊ | Latin Capital Letter O with Loop | JZ | Jump to the address at the top of the stack, if the 2nd-top value is zero |
| โ | Bullseye | LOAD | Pop from the stack, and push the value at the memory address specified |
| โฏ | Large Circle | STORE | Pop the top two values from the stack, storing the 2nd at the address specified by the 1st |
| โช | Parenthesized Latin Small Letter O | READ | Read the next byte from stdin, pushing it to the top of the stack, or 0 if stdin is empty |
| โ | Latin Subscript Small Letter O | WRITE | Pop from the stack and write the value to stdin as an ascii character |
The language and interpreter are written in Rust. The compiled binary executable acts as a command line program, but the interpreter crate also exposes a public API. When compiled to webassembly, this API is used to provide functionality for the Web IDE within the browser.