# OOLANG

OOLANG is an esoteric stack-based programming language where all instructions/commands are differnet unicode O characters
## Usage
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`.
## Language Specification
OOLANG emulates a [stack machine](https://en.wikipedia.org/wiki/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:
| `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 |
## Architecture
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.