From 56c80b9aaff7dd7e94c05f1c967cfbac0ee3a8bc Mon Sep 17 00:00:00 2001
From: Pekka Laiho <pekka.i.laiho@gmail.com>
Date: Wed, 27 May 2020 20:48:31 +0700
Subject: [PATCH] improvements

---
 classes.php | 10 +++---
 lib.php     | 92 +++++++++++++++++++++++++++++++++++++++++++++++++++--
 lisp.php    | 19 +++++++++--
 3 files changed, 112 insertions(+), 9 deletions(-)

diff --git a/classes.php b/classes.php
index 7c35663..17ff3a8 100644
--- a/classes.php
+++ b/classes.php
@@ -49,11 +49,6 @@ class MLHash extends MLCollection
 
         throw new MadLispException("hash does not contain key $key");
     }
-
-    public function set(string $key, $value): void
-    {
-        $this->data[$key] = $value;
-    }
 }
 
 class MLEnv extends MLHash
@@ -75,6 +70,11 @@ class MLEnv extends MLHash
 
         throw new MadLispException("symbol $key not defined");
     }
+
+    public function set(string $key, $value): void
+    {
+        $this->data[$key] = $value;
+    }
 }
 
 class MLSymbol
diff --git a/lib.php b/lib.php
index f68e953..b55156a 100644
--- a/lib.php
+++ b/lib.php
@@ -6,7 +6,35 @@ function ml_get_env(): MLEnv
 {
     $env = new MLEnv();
 
-    // basic arithmetic
+    // logic
+
+    $env->set('or', function (...$args) {
+        // return first true
+        for ($i = 0; $i < count($args) - 1; $i++) {
+            if ($args[$i] == true) {
+                return $args[$i];
+            }
+        }
+
+        // return last
+        return $args[count($args) - 1];
+    });
+
+    $env->set('and', function (...$args) {
+        // return first false
+        for ($i = 0; $i < count($args) - 1; $i++) {
+            if ($args[$i] == false) {
+                return $args[$i];
+            }
+        }
+
+        // return last
+        return $args[count($args) - 1];
+    });
+
+    $env->set('not', fn ($a) => !$a);
+
+    // arithmetic
 
     $env->set('+', function (...$args) {
         return array_sum($args);
@@ -56,8 +84,68 @@ function ml_get_env(): MLEnv
     // types
 
     $env->set('type?', function ($a) {
-        return gettype($a);
+        if ($a instanceof Closure) {
+            return 'function';
+        } elseif ($a instanceof MLList) {
+            return 'list';
+        } elseif ($a instanceof MLHash) {
+            return 'hash';
+        } elseif ($a instanceof MLSymbol) {
+            return 'symbol';
+        } elseif ($a === true || $a === false) {
+            return 'bool';
+        } elseif ($a === null) {
+            return 'null';
+        } elseif (is_int($a)) {
+            return 'int';
+        } elseif (is_float($a)) {
+            return 'float';
+        } else {
+            return 'string';
+        }
     });
 
+    $env->set('fn?', fn ($a) => $a instanceof Closure);
+    $env->set('list?', fn ($a) => $a instanceof MLList);
+    $env->set('hash?', fn ($a) => $a instanceof MLHash);
+    $env->set('sym?', fn ($a) => $a instanceof MLSymbol);
+    $env->set('bool?', fn ($a) => $a === true || $a === false);
+    $env->set('true?', fn ($a) => $a == true); // not strict
+    $env->set('false?', fn ($a) => $a == false); // not strict
+    $env->set('null?', fn ($a) => $a === null);
+    $env->set('int?', fn ($a) => is_int($a));
+    $env->set('float?', fn ($a) => is_float($a));
+    $env->set('str?', fn ($a) => is_string($a));
+
+    // collections
+
+    $env->set('list', function (...$args) {
+        return new MLList($args);
+    });
+
+    $env->set('hash', function (...$args) {
+        if (count($args) % 2 == 1) {
+            throw new MadLispException('uneven number of arguments for hash');
+        }
+
+        $data = [];
+
+        for ($i = 0; $i < count($args) - 1; $i += 2) {
+            $key = $args[$i];
+            $val = $args[$i + 1];
+
+            if (!is_string($key)) {
+                throw new MadLispException('invalid key for hash (not string)');
+            }
+
+            $data[$key] = $val;
+        }
+
+        return new MLHash($data);
+    });
+
+    // for debugging!
+    $env->set('eval', fn ($a) => ml_eval($a, $env));
+
     return $env;
 }
diff --git a/lisp.php b/lisp.php
index b7784a7..1acd136 100644
--- a/lisp.php
+++ b/lisp.php
@@ -149,14 +149,23 @@ function ml_eval($expr, MLEnv $env)
         // Evaluate list contents
         $results = array_map(fn ($a) => ml_eval($a, $env), $expr->getData());
 
-        if ($results[0] instanceof Closure) {
+        $fn = $results[0];
+
+        if ($fn instanceof Closure) {
             // If the first item is a function, call it
             $args = array_slice($results, 1);
-            return ($results[0])(...$args);
+            return $fn(...$args);
         } else {
             // Otherwise return new list with evaluated contents
             return new MLList($results);
         }
+    } elseif ($expr instanceof MLHash) {
+        // Hash: return new hash with all items evaluated
+        $items = [];
+        foreach ($expr->getData() as $key => $val) {
+            $items[$key] = ml_eval($val, $env);
+        }
+        return new MLHash($items);
     } elseif ($expr instanceof MLSymbol) {
         return $env->get($expr->name());
     }
@@ -170,6 +179,12 @@ function ml_print($a): string
         return '<function>';
     } elseif ($a instanceof MLList) {
         return '(' . implode(' ', array_map('ml_print', $a->getData())) . ')';
+    } elseif ($a instanceof MLHash) {
+        $items = [];
+        foreach ($a->getData() as $key => $val) {
+            $items[] = ml_print($key) . ':' . ml_print($val);
+        }
+        return '{' . implode(' ', $items) . '}';
     } elseif ($a instanceof MLSymbol) {
         return $a->name();
     } elseif ($a === true) {