scl/README.md

# SCL: Simple CAS Language

Version v1.0-alpha

## Usage

```bash
git clone https://git.signorovitch.org/jacob/scl -b stable
cd scl
make release
./scl.out
```

### For Development

```bash
git clone git@signorovitch.org:jacob/scl --recurse-submodules && cd scl
make all test
./scl.out
```

If you wish to run tests, make sure to run `git clone --recurse-submodules` to
include the [Unity](https://github.com/ThrowTheSwitch/Unity) test framework.

## Current State

See [STATUS.md](STATUS.md). Currently, one is able to use `scl` as a basic,
interactive, four-function calculator.

## Syntax (Planned)

As one would expect, you can evaluate simple infix expressions:

```scl
> 1 + 1
= 2
```

You can also define your own functions:

```scl
> f(x) = 2x
> f(2)
= 4
```

Symbolic algebra is done in the following manner:

```scl
> f(x) = x^4
> diff(f, x:sym, 2)
= 12x^2
```

SCL will dynamically decide on types, but you can state them explicitly as
well:

```scl
> f(x:int) = 2x
> f(2.2)
! f(x:int): x must be of type int.
```

Variables can be defined, with several attributes:

```scl
> a = 1             // Interpret type automatically.
> b:int = 1         // Must be int.
> c:const:int = 1   // Constant: value can never change.
> x:sym             // Treated symbolicaly.
```