From 72dc10f3698f9a5ef777350364b66347e1175891 Mon Sep 17 00:00:00 2001
From: Pekka Laiho <pekka.i.laiho@gmail.com>
Date: Sat, 17 Oct 2020 14:47:30 +0700
Subject: [PATCH] add function: exit

---
 README.md           | 1 +
 src/LispFactory.php | 6 ++++++
 2 files changed, 7 insertions(+)

diff --git a/README.md b/README.md
index be9794d..a2042d5 100644
--- a/README.md
+++ b/README.md
@@ -144,6 +144,7 @@ doc   | `(doc +)` | `"Return the sum of all arguments."` | Show description of a
 read  | `(read "(+ 1 2 3)")` | `(+ 1 2 3)` | Read a string as code and return the expression.
 print | `(print "hello world")` | `"hello world"null` | Print expression on the screen. Print returns null (which is shown due to the extra print in repl). Give optional second argument as `true` to show strings in readable format.
 error | `(error "invalid value")` | `error: invalid value` | Throw an exception with message as argument.
+exit  | `(exit 1)` | | Terminate the script with given exit code using [exit](https://www.php.net/manual/en/function.exit.php).
 
 ### Collection functions
 
diff --git a/src/LispFactory.php b/src/LispFactory.php
index 2027d01..b562b5c 100644
--- a/src/LispFactory.php
+++ b/src/LispFactory.php
@@ -41,6 +41,12 @@ class LispFactory
             }
         ));
 
+        $env->set('exit', new CoreFunc('exit', 'Terminate the script with given exit code.', 0, 1,
+            function ($status = 0) {
+                exit($status);
+            }
+        ));
+
         // Register core libraries
         (new Lib\Collections())->register($env);
         (new Lib\Compare())->register($env);