Fix metadata on functions.

- Don't use metadata to store ast, env, params data. - In Clojure, store metadata on the :meta key of the real metadata. This also allows using any datatype as metadata.
Aegwenia · Apr 10, 2014 · a34b020 · a34b020
1 parent edc3b06
commit a34b020
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Showing 37 changed files with 183 additions and 139 deletions.
diff --git a/clojure/src/core.clj b/clojure/src/core.clj
@@ -4,6 +4,16 @@
 (defn mal_throw [obj]
   (throw (ex-info "mal exception" {:data obj})))
 
+;; Metadata
+;; - store metadata at :meta key of the real metadata
+(defn mal_with_meta [obj m]
+  (let [new-meta (assoc (meta obj) :meta m)]
+    (with-meta obj new-meta)))
+
+(defn mal_meta [obj]
+  (:meta (meta obj)))
+
+
 ;; Atoms
 (defn atom? [atm]
   (= (type atm) clojure.lang.Atom))
@@ -54,8 +64,8 @@
    ['apply apply]
    ['map #(doall (map %1 %2))] 
 
-   ['with-meta with-meta]
-   ['meta meta]
+   ['with-meta mal_with_meta]
+   ['meta mal_meta]
    ['atom atom]
    ['atom? atom?]
    ['deref deref]

diff --git a/clojure/src/step0_repl.clj b/clojure/src/step0_repl.clj
@@ -12,13 +12,12 @@
   (eval (read-string ast)))
 
 ;; print
-(defn PRINT [exp]
-  exp)
+(defn PRINT [exp] exp)
 
 ;; repl
 (defn rep [strng] (PRINT (EVAL (READ strng), {})))
 
-(defn -main [& args] 
+(defn -main [& args]
   (loop []
     (let [line (readline/readline "user> ")]
       (when line

diff --git a/clojure/src/step1_read_print.clj b/clojure/src/step1_read_print.clj
@@ -19,7 +19,7 @@
 ;; repl
 (defn rep
   [strng]
-  (PRINT (EVAL (READ strng), {})))
+  (PRINT (EVAL (READ strng) {})))
 
 (defn -main [& args]
   (loop []

diff --git a/clojure/src/step2_eval.clj b/clojure/src/step2_eval.clj
@@ -46,7 +46,7 @@
                '/ /})
 (defn rep
   [strng]
-  (PRINT (EVAL (READ strng), repl-env)))
+  (PRINT (EVAL (READ strng) repl-env)))
 
 (defn -main [& args]
   (loop []

diff --git a/clojure/src/step3_env.clj b/clojure/src/step3_env.clj
@@ -55,7 +55,7 @@
 (def repl-env (env/env))
 (defn rep
   [strng]
-  (PRINT (EVAL (READ strng), repl-env)))
+  (PRINT (EVAL (READ strng) repl-env)))
 
 (defn _ref [k,v] (env/env-set repl-env k v))
 (_ref '+ +)

diff --git a/clojure/src/step4_if_fn_do.clj b/clojure/src/step4_if_fn_do.clj
@@ -71,7 +71,7 @@
 (def repl-env (env/env))
 (defn rep
   [strng]
-  (PRINT (EVAL (READ strng), repl-env)))
+  (PRINT (EVAL (READ strng) repl-env)))
 
 (defn _ref [k,v] (env/env-set repl-env k v))
 

diff --git a/clojure/src/step5_tco.clj b/clojure/src/step5_tco.clj
@@ -58,11 +58,12 @@
               (recur a2 env)))
 
           'fn*
-          ^{:expression a2
-            :environment env
-            :parameters a1}
-          (fn [& args]
-            (EVAL a2 (env/env env a1 args)))
+          (with-meta
+            (fn [& args]
+              (EVAL a2 (env/env env a1 args)))
+            {:expression a2
+             :environment env
+             :parameters a1})
 
           ;; apply
           (let [el (eval-ast ast env)
@@ -80,7 +81,7 @@
 (def repl-env (env/env))
 (defn rep
   [strng]
-  (PRINT (EVAL (READ strng), repl-env)))
+  (PRINT (EVAL (READ strng) repl-env)))
 
 (defn _ref [k,v] (env/env-set repl-env k v))
 

diff --git a/clojure/src/step6_file.clj b/clojure/src/step6_file.clj
@@ -58,11 +58,12 @@
               (recur a2 env)))
 
           'fn*
-          ^{:expression a2
-            :environment env
-            :parameters a1}
-          (fn [& args]
-            (EVAL a2 (env/env env a1 args)))
+          (with-meta
+            (fn [& args]
+              (EVAL a2 (env/env env a1 args)))
+            {:expression a2
+             :environment env
+             :parameters a1})
 
           ;; apply
           (let [el (eval-ast ast env)

diff --git a/clojure/src/step7_quote.clj b/clojure/src/step7_quote.clj
@@ -81,11 +81,12 @@
               (recur a2 env)))
 
           'fn*
-          ^{:expression a2
-            :environment env
-            :parameters a1}
-          (fn [& args]
-            (EVAL a2 (env/env env a1 args)))
+          (with-meta
+            (fn [& args]
+              (EVAL a2 (env/env env a1 args)))
+            {:expression a2
+             :environment env
+             :parameters a1})
 
           ;; apply
           (let [el (eval-ast ast env)

diff --git a/clojure/src/step8_macros.clj b/clojure/src/step8_macros.clj
@@ -107,11 +107,12 @@
                   (recur a2 env)))
 
               'fn*
-              ^{:expression a2
-                :environment env
-                :parameters a1}
-              (fn [& args]
-                (EVAL a2 (env/env env a1 args)))
+              (with-meta
+                (fn [& args]
+                  (EVAL a2 (env/env env a1 args)))
+                {:expression a2
+                 :environment env
+                 :parameters a1})
 
               ;; apply
               (let [el (eval-ast ast env)

diff --git a/clojure/src/step9_interop.clj b/clojure/src/step9_interop.clj
@@ -110,11 +110,12 @@
                   (recur a2 env)))
 
               'fn*
-              ^{:expression a2
-                :environment env
-                :parameters a1}
-              (fn [& args]
-                (EVAL a2 (env/env env a1 args)))
+              (with-meta
+                (fn [& args]
+                  (EVAL a2 (env/env env a1 args)))
+                {:expression a2
+                 :environment env
+                 :parameters a1})
 
               ;; apply
               (let [el (eval-ast ast env)

diff --git a/clojure/src/stepA_more.clj b/clojure/src/stepA_more.clj
@@ -124,11 +124,12 @@
                   (recur a2 env)))
 
               'fn*
-              ^{:expression a2
-                :environment env
-                :parameters a1}
-              (fn [& args]
-                (EVAL a2 (env/env env a1 args)))
+              (with-meta
+                (fn [& args]
+                  (EVAL a2 (env/env env a1 args)))
+                {:expression a2
+                 :environment env
+                 :parameters a1})
 
               ;; apply
               (let [el (eval-ast ast env)

diff --git a/docs/TODO b/docs/TODO
@@ -80,10 +80,11 @@ Future Implementations:
             * JavaScript
             * Java
             * PHP
-            - C#
+            * C#
             * Python
             - C++
             - Ruby
+                - http://www.ruby-doc.org/stdlib-1.9.3/libdoc/readline/rdoc/Readline.html
             * C
             - Objective-C
             - Perl 
@@ -116,8 +117,6 @@ Future Implementations:
                 - https://github.com/tpope/timl
             - Common Lisp
             - Rust
-
-        - Tier 4
             - M (OpenM/MUMPS)
             - Factor (Stack-based)
 

diff --git a/js/step5_tco.js b/js/step5_tco.js
@@ -69,9 +69,9 @@ function _EVAL(ast, env) {
         return types._function(EVAL, Env, a2, env, a1);
     default:
         var el = eval_ast(ast, env), f = el[0], meta = f.__meta__;
-        if (meta && meta.exp) {
-            ast = meta.exp;
-            env = new Env(meta.env, meta.params, el.slice(1));
+        if (f.__ast__) {
+            ast = f.__ast__;
+            env = f.__gen_env__(el.slice(1));
         } else {
             return f.apply(f, el.slice(1));
         }

diff --git a/js/step6_file.js b/js/step6_file.js
@@ -69,9 +69,9 @@ function _EVAL(ast, env) {
         return types._function(EVAL, Env, a2, env, a1);
     default:
         var el = eval_ast(ast, env), f = el[0], meta = f.__meta__;
-        if (meta && meta.exp) {
-            ast = meta.exp;
-            env = new Env(meta.env, meta.params, el.slice(1));
+        if (f.__ast__) {
+            ast = f.__ast__;
+            env = f.__gen_env__(el.slice(1));
         } else {
             return f.apply(f, el.slice(1));
         }

diff --git a/js/step7_quote.js b/js/step7_quote.js
@@ -89,9 +89,9 @@ function _EVAL(ast, env) {
         return types._function(EVAL, Env, a2, env, a1);
     default:
         var el = eval_ast(ast, env), f = el[0], meta = f.__meta__;
-        if (meta && meta.exp) {
-            ast = meta.exp;
-            env = new Env(meta.env, meta.params, el.slice(1));
+        if (f.__ast__) {
+            ast = f.__ast__;
+            env = f.__gen_env__(el.slice(1));
         } else {
             return f.apply(f, el.slice(1));
         }

diff --git a/js/step8_macros.js b/js/step8_macros.js
@@ -113,9 +113,9 @@ function _EVAL(ast, env) {
         return types._function(EVAL, Env, a2, env, a1);
     default:
         var el = eval_ast(ast, env), f = el[0], meta = f.__meta__;
-        if (meta && meta.exp) {
-            ast = meta.exp;
-            env = new Env(meta.env, meta.params, el.slice(1));
+        if (f.__ast__) {
+            ast = f.__ast__;
+            env = f.__gen_env__(el.slice(1));
         } else {
             return f.apply(f, el.slice(1));
         }

diff --git a/js/step9_interop.js b/js/step9_interop.js
@@ -119,9 +119,9 @@ function _EVAL(ast, env) {
         return types._function(EVAL, Env, a2, env, a1);
     default:
         var el = eval_ast(ast, env), f = el[0], meta = f.__meta__;
-        if (meta && meta.exp) {
-            ast = meta.exp;
-            env = new Env(meta.env, meta.params, el.slice(1));
+        if (f.__ast__) {
+            ast = f.__ast__;
+            env = f.__gen_env__(el.slice(1));
         } else {
             return f.apply(f, el.slice(1));
         }

diff --git a/js/stepA_more.js b/js/stepA_more.js
@@ -130,9 +130,9 @@ function _EVAL(ast, env) {
         return types._function(EVAL, Env, a2, env, a1);
     default:
         var el = eval_ast(ast, env), f = el[0], meta = f.__meta__;
-        if (meta && meta.exp) {
-            ast = meta.exp;
-            env = new Env(meta.env, meta.params, el.slice(1));
+        if (f.__ast__) {
+            ast = f.__ast__;
+            env = f.__gen_env__(el.slice(1));
         } else {
             return f.apply(f, el.slice(1));
         }

diff --git a/js/types.js b/js/types.js
@@ -100,14 +100,14 @@ function _symbol_Q(obj) { return obj instanceof Symbol; }
 
 
 // Functions
-function _function(Eval, Env, exp, env, params) {
-    var f = function() {
-        // TODO: figure out why this throws with 'and' macro
-        //throw new Error("Attempt to invoke mal function directly");
-        return Eval(exp, new Env(env, params, arguments));
+function _function(Eval, Env, ast, env, params) {
+    var fn = function() {
+        return Eval(ast, new Env(env, params, arguments));
     };
-    f.__meta__ = {exp: exp, env: env, params: params};
-    return f;
+    fn.__meta__ = null;
+    fn.__ast__ = ast;
+    fn.__gen_env__ = function(args) { return new Env(env, params, args); };
+    return fn;
 }
 function _function_Q(obj) { return typeof obj == "function"; }
 Function.prototype.clone = function() {

diff --git a/php/step5_tco.php b/php/step5_tco.php
@@ -72,16 +72,14 @@ function MAL_EVAL($ast, $env) {
         break;
     case "fn*":
         return _function('MAL_EVAL', 'native',
-                         _hash_map('exp', $ast[2],
-                                   'env', $env,
-                                   'params', $ast[1]));
+                         $ast[2], $env, $ast[1]);
     default:
         $el = eval_ast($ast, $env);
         $f = $el[0];
         $args = array_slice($el->getArrayCopy(), 1);
         if ($f->type === 'native') {
-            $ast = $f->meta['exp'];
-            $env = new Env($f->meta['env'], $f->meta['params'], $args);
+            $ast = $f->ast;
+            $env = $f->gen_env($args);
         } else {
             return $f->apply($args);
         }

diff --git a/php/step6_file.php b/php/step6_file.php
@@ -72,16 +72,14 @@ function MAL_EVAL($ast, $env) {
         break;
     case "fn*":
         return _function('MAL_EVAL', 'native',
-                         _hash_map('exp', $ast[2],
-                                   'env', $env,
-                                   'params', $ast[1]));
+                         $ast[2], $env, $ast[1]);
     default:
         $el = eval_ast($ast, $env);
         $f = $el[0];
         $args = array_slice($el->getArrayCopy(), 1);
         if ($f->type === 'native') {
-            $ast = $f->meta['exp'];
-            $env = new Env($f->meta['env'], $f->meta['params'], $args);
+            $ast = $f->ast;
+            $env = $f->gen_env($args);
         } else {
             return $f->apply($args);
         }

diff --git a/php/step7_quote.php b/php/step7_quote.php
@@ -95,16 +95,14 @@ function MAL_EVAL($ast, $env) {
         break;
     case "fn*":
         return _function('MAL_EVAL', 'native',
-                         _hash_map('exp', $ast[2],
-                                   'env', $env,
-                                   'params', $ast[1]));
+                         $ast[2], $env, $ast[1]);
     default:
         $el = eval_ast($ast, $env);
         $f = $el[0];
         $args = array_slice($el->getArrayCopy(), 1);
         if ($f->type === 'native') {
-            $ast = $f->meta['exp'];
-            $env = new Env($f->meta['env'], $f->meta['params'], $args);
+            $ast = $f->ast;
+            $env = $f->gen_env($args);
         } else {
             return $f->apply($args);
         }

diff --git a/php/step8_macros.php b/php/step8_macros.php
@@ -120,16 +120,14 @@ function MAL_EVAL($ast, $env) {
         break;
     case "fn*":
         return _function('MAL_EVAL', 'native',
-                         _hash_map('exp', $ast[2],
-                                   'env', $env,
-                                   'params', $ast[1]));
+                         $ast[2], $env, $ast[1]);
     default:
         $el = eval_ast($ast, $env);
         $f = $el[0];
         $args = array_slice($el->getArrayCopy(), 1);
         if ($f->type === 'native') {
-            $ast = $f->meta['exp'];
-            $env = new Env($f->meta['env'], $f->meta['params'], $args);
+            $ast = $f->ast;
+            $env = $f->gen_env($args);
         } else {
             return $f->apply($args);
         }