# Pipple

Pipple is a simple Lisp-family programming language.

## Getting started

Pipple builds with CMake. Run the following to build Pipple:

```shell
cmake -B build -DCMAKE_BUILD_TYPE=Release
cmake --build build
```

The `pipple` executable will be placed in the build folder.

## Coding with Pipple

Pipple's interpreter provides a REPL for fast prototyping. Try it out by running the `pipple` command without any arguments.

```
$ ./build/pipple
pipple> 
```

Pipple code you write will be run now. Try something like `(print "Hello, World!")`. See what happens!

If you'd like to use Pipple with a file, just add the filename after the executable path.

## Syntax

Pipple's syntax looks like most other Lisps. You enclose your statements in `(` and `)`.

### Printing

```
(print "Hello, World!")
(print 32)
(print 3.141)
```

### Setting and Changing Variables

```
(let x 3.141)
(print x)
(set x 2.712)
(print x)
```

### Math

Remember: Polish notation is the key!

```
(let x (+ 3 4))
(print x)

(let y (* 5 6 2))
(print y)

(print (/ 10 2))

(print (- 10 5))
```

### Conditionals

```
(let x 0)
(if (== x 0)
    (print "x is zero")
    (set x 1)
    (print "now it is" x)
)

(while (!= x 5)
    (print "x is currently" x "which is not 5. i must make it 5")
    (set x (+ x 1))
)
(print "now x is" x)
```

### User console input

```
(let x (input))
(print "You said" x)
```