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README.md

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+# MadLisp
+
+MadLisp is a [Lisp](https://en.wikipedia.org/wiki/Lisp_%28programming_language%29) interpreter written in PHP. It is inspired by the [Make a Lisp](https://github.com/kanaka/mal) project, but does not follow that convention or syntax strictly.
+
+## Requirements
+
+The project does use syntax of PHP 7.4 so that version or newer is required.
+
+The project does not have any dependencies to external [Composer](https://getcomposer.org/) libraries, but it does use Composer for the autoloader so you need to run **composer install** for that.
+
+## Usage
+
+Use the **run.php** file to invoke the interpreter. You can invoke the Repl with the -r switch:
+
+```
+$ php run.php -r
+```
+
+You can also evaluate code directly with the -e switch:
+
+```
+$ php run.php -e "(+ 1 2 3)"
+6
+```
+
+Or you can evaluate a file with the -f switch:
+
+```
+$ php run.php -f file.mad
+```
+
+## Special forms
+
+## Core functions
+
+Name  | Example | Description
+----- | ------- | -----------
+doc   | (doc +) | Show description of a built-in function.
+read  | (read "(+ 1 2 3)") | Read a string as code and return the expression.
+print | (print "hello world") | Print expression on the screen.
+error | (error "invalid value") | Throw an exception with message as argument.
+
+## License
+
+[MIT](https://choosealicense.com/licenses/mit/)