All: split types into types, env, printer, core.

- types: low-level mapping to the implementation language.
- core: functions on types that are exposed directly to mal.
- printer: implementation called by pr-str, str, prn, println.
- env: the environment implementation

- Also, unindent all TCO while loops so that the diff of step4 and
  step5 are minimized.

1 files changed, 53 insertions, 0 deletions

diff --git a/php/printer.php b/php/printer.php
new file mode 100644
index 0000000..3839931
--- /dev/null
+++ b/php/printer.php
@@ -0,0 +1,53 @@
+<?php
+
+require_once 'types.php';
+
+function _pr_str($obj, $print_readably=True) {
+    if (_list_Q($obj)) {
+        $ret = array();
+        foreach ($obj as $e) {
+            array_push($ret, _pr_str($e, $print_readably));
+        }
+        return "(" . implode(" ", $ret) . ")";
+    } elseif (_vector_Q($obj)) {
+        $ret = array();
+        foreach ($obj as $e) {
+            array_push($ret, _pr_str($e, $print_readably));
+        }
+        return "[" . implode(" ", $ret) . "]";
+    } elseif (_hash_map_Q($obj)) {
+        $ret = array();
+        foreach (array_keys($obj->getArrayCopy()) as $k) {
+            $ret[] = _pr_str($k, $print_readably);
+            $ret[] = _pr_str($obj[$k], $print_readably);
+        }
+        return "{" . implode(" ", $ret) . "}";
+    } elseif (is_string($obj)) {
+        if ($print_readably) {
+            $obj = preg_replace('/"/', '\\"', preg_replace('/\\\\/', '\\\\\\\\', $obj));
+            return '"' . $obj . '"';
+        } else {
+            return $obj;
+        }
+    } elseif (is_integer($obj)) {
+        return $obj;
+    } elseif ($obj === NULL) {
+        return "nil";
+    } elseif ($obj === true) {
+        return "true";
+    } elseif ($obj === false) {
+        return "false";
+    } elseif (_symbol_Q($obj)) {
+        return $obj->value;
+    } elseif (_atom_Q($obj)) {
+        return "(atom " . _pr_str($obj->value, $print_readably) . ")";
+    } elseif (_function_Q($obj)) {
+        return "(fn* [...] ...)";
+    } elseif (is_callable($obj)) {  // only step4 and below
+        return "#<function ...>";
+    } else {
+        throw new Exception("_pr_str unknown type: " . gettype($obj));
+    }
+}
+
+?>