79 lines
1.6 KiB
Markdown
79 lines
1.6 KiB
Markdown
# SCL: Simple CAS Language
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Version v1.0-alpha
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SCL aims to be a human-friendly Computer Algebra System (CAS) inspired by
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[maxima](https://maxima.sourceforge.io/) that feels like writing on paper. In
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its current state, SCL can be used as a basic 4-function calculator with order
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of operations and local variables. The codebase is about 1,400 lines of C,
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including a parser, interpreter, and runtime.
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## Usage
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To download and run:
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```bash
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git clone https://git.signorovitch.org/jacob/scl -b stable && cd scl
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make release
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./scl.out
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```
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### For Development
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```bash
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git clone git@signorovitch.org:jacob/scl --recurse-submodules && cd scl
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make all test
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./scl.out
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```
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If you wish to run tests, make sure to run `git clone --recurse-submodules` to
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include the [Unity](https://github.com/ThrowTheSwitch/Unity) test framework.
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## Syntax
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As one would expect, you can evaluate simple infix expressions:
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```scl
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> 1 + 1
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= 2
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```
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You can also define your own functions and variables:
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```scl
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> f(x) = 2x
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> n = 3
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> f(n)
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= 6
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```
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Symbolic algebra is done in the following manner:
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```scl
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> f(x) = x^4
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> diff(f, x:sym, 2)
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= 12x^2
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```
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SCL will dynamically decide on types, but you can state them explicitly as
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well:
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```scl
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> f(x: int): int = 2x
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> f(3)
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= 6
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> f(3.1)
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! Traceback:
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! In call to `f(x: int): int`:
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! TypeError (58): Argument `x` must be of type `int`.
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```
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Variables can be defined, with several attributes:
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```scl
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> a = 1 // Interpret type automatically.
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> b:int = 1 // Must be int.
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> c:const:int = 1 // Constant: value can never change.
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> x:sym // Treated symbolicaly.
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```
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