Merge pull request #918 from hellerve/veit/static-args

core: use static array for args

core/System.carp

@@ -16,10 +16,8 @@
   (register sleep-micros (Fn [Int] ()))
   (doc system "Performs a system command.")
   (register system (Fn [&String] Int))
-  (doc get-arg "Gets the command line argument at a specified index.")
-  (register get-arg (Fn [Int] (Ref String)))
-  (doc get-args-len "Gets the number of command line arguments.")
-  (register get-args-len (Fn [] Int))
+  (doc args "Represents the command line arguments.")
+  (register args (StaticArray String))
   (register fork (Fn [] Int) "fork")
   (register wait (Fn [(Ptr Int)] Int) "wait")
   (register get-exit-status (Fn [Int] Int) "WEXITSTATUS")

core/carp_string.h

@@ -183,7 +183,7 @@ Array String_to_MINUS_bytes(const String *s) {
 String String_from_MINUS_bytes(Array *a) {
     String s;
     const char *us = (const char *)a->data;
-    s = CARP_MALLOC(a->len+1);
+    s = CARP_MALLOC(a->len + 1);
     memcpy(s, us, a->len);
     s[a->len] = '\0';
     return s;

core/carp_system.h

@@ -40,12 +40,3 @@ int System_system(const String *command) {
 }
 
 Array System_args;
-
-String *System_get_MINUS_arg(int idx) {
-    assert(idx < System_args.len);
-    return &(((String *)System_args.data)[idx]);
-}
-
-int System_get_MINUS_args_MINUS_len() {
-    return System_args.len;
-}

docs/core/System.html

@@ -523,6 +523,26 @@
                     
                 </p>
             </div>
+            <div class="binder">
+                <a class="anchor" href="#args">
+                    <h3 id="args">
+                        args
+                    </h3>
+                </a>
+                <div class="description">
+                    external
+                </div>
+                <p class="sig">
+                    (StaticArray String)
+                </p>
+                <span>
+                    
+                </span>
+                <p class="doc">
+                    <p>Represents the command line arguments.</p>
+
+                </p>
+            </div>
             <div class="binder">
                 <a class="anchor" href="#carp-init-globals">
                     <h3 id="carp-init-globals">
@@ -621,46 +641,6 @@
 
                 </p>
             </div>
-            <div class="binder">
-                <a class="anchor" href="#get-arg">
-                    <h3 id="get-arg">
-                        get-arg
-                    </h3>
-                </a>
-                <div class="description">
-                    external
-                </div>
-                <p class="sig">
-                    (Fn [Int] (Ref String a))
-                </p>
-                <span>
-                    
-                </span>
-                <p class="doc">
-                    <p>Gets the command line argument at a specified index.</p>
-
-                </p>
-            </div>
-            <div class="binder">
-                <a class="anchor" href="#get-args-len">
-                    <h3 id="get-args-len">
-                        get-args-len
-                    </h3>
-                </a>
-                <div class="description">
-                    external
-                </div>
-                <p class="sig">
-                    (Fn [] Int)
-                </p>
-                <span>
-                    
-                </span>
-                <p class="doc">
-                    <p>Gets the number of command line arguments.</p>
-
-                </p>
-            </div>
             <div class="binder">
                 <a class="anchor" href="#get-exit-status">
                     <h3 id="get-exit-status">

src/Eval.hs

@@ -39,6 +39,19 @@ import qualified Meta
 import Debug.Trace
 
 -- | Dynamic (REPL) evaluation of XObj:s (s-expressions)
+-- Note: You might find a bunch of code of the following form both here and in
+-- macroExpand:
+--
+-- return (ctx, do res <- <something>
+--                 Right <something else with res>)
+--
+-- This might a little weird to you, and rightfully so. Through the nested do
+-- we ensure that an evaluation is forced where it needs to be, since we depend
+-- on the state here; eval is inherently stateful (because it carries around
+-- the compiler’s context, which might change after each macro expansion), and
+-- it gets real weird with laziness. (Note to the note: this code is mostly a
+-- remnant of us using StateT, and might not be necessary anymore since we
+-- switched to more explicit state-passing.)
 eval :: Context -> XObj -> IO (Context, Either EvalError XObj)
 eval ctx xobj@(XObj o i t) =
   case o of
@@ -75,6 +88,10 @@ eval ctx xobj@(XObj o i t) =
       (newCtx, evaled) <- foldlM successiveEval (ctx, Right []) objs
       return (newCtx, do ok <- evaled
                          Right (XObj (Arr ok) i t))
+    StaticArr objs  -> do
+      (newCtx, evaled) <- foldlM successiveEval (ctx, Right []) objs
+      return (newCtx, do ok <- evaled
+                         Right (XObj (StaticArr ok) i t))
     _        -> return (ctx, Right xobj)
   where
     resolveDef (XObj (Lst [XObj DefDynamic _ _, _, value]) _ _) = value
@@ -293,6 +310,10 @@ macroExpand ctx xobj =
       (newCtx, expanded) <- foldlM successiveExpand (ctx, Right []) objs
       return (newCtx, do ok <- expanded
                          Right (XObj (Arr ok) i t))
+    XObj (StaticArr objs) i t -> do
+      (newCtx, expanded) <- foldlM successiveExpand (ctx, Right []) objs
+      return (newCtx, do ok <- expanded
+                         Right (XObj (StaticArr ok) i t))
     XObj (Lst [XObj (Lst (XObj Macro _ _:_)) _ _]) _ _ -> eval ctx xobj
     XObj (Lst (x@(XObj sym@(Sym s _) _ _):args)) i t -> do
       (newCtx, f) <- eval ctx x

test/args.carp

@@ -12,10 +12,6 @@
 
 (deftest test
   (assert-equal test
-               1
-               (System.get-args-len)
-               "System.get-args-len works as expected")
-  (assert-equal test
-                (make-exe-path "Untitled")
-                (System.get-arg 0)
-                "System.get-arg works as expected"))
+                $[@(make-exe-path "Untitled")]
+                &System.args
+                "System.args works as expected"))