- The compiler now stores the cursor of the last analysed AST in order to avoid the problem of error ocurring "nowhere" (at ["" -1 -1]).

3 files changed, 49 insertions, 30 deletions

diff --git a/src/lux/analyser.clj b/src/lux/analyser.clj
index 774188d82..d18c2cfcf 100644
--- a/src/lux/analyser.clj
+++ b/src/lux/analyser.clj
@@ -501,10 +501,10 @@
         (return* state* output)
 
         [["lux;Left" ""]]
-        (fail* (add-loc meta (str "[Analyser Error] Unrecognized token: " (&/show-ast token))))
+        (fail* (add-loc (&/get$ &/$cursor state) (str "[Analyser Error] Unrecognized token: " (&/show-ast token))))
 
         [["lux;Left" msg]]
-        (fail* (add-loc meta msg))
+        (fail* (add-loc (&/get$ &/$cursor state) msg))
         ))
 
     ;; [_]
@@ -527,25 +527,26 @@
         ))))
 
 (defn ^:private analyse-ast [eval! compile-module compile-token exo-type token]
-  (&/with-expected-type exo-type
-    (matchv ::M/objects [token]
-      [["lux;Meta" [meta ["lux;FormS" ["lux;Cons" [["lux;Meta" [_ ["lux;TagS" ?ident]]] ?values]]]]]]
-      (&&lux/analyse-variant (partial analyse-ast eval! compile-module compile-token) exo-type ?ident ?values)
-      
-      [["lux;Meta" [meta ["lux;FormS" ["lux;Cons" [?fn ?args]]]]]]
-      (fn [state]
-        (matchv ::M/objects [((just-analyse (partial analyse-ast eval! compile-module compile-token) ?fn) state)
-                             ;; ((&type/with-var #(&&/analyse-1 (partial analyse-ast eval! compile-module) % ?fn)) state)
-                             ]
-          [["lux;Right" [state* =fn]]]
-          (do ;; (prn 'GOT_FUN (&/show-ast ?fn) (&/show-ast token) (aget =fn 0 0) (aget =fn 1 0))
-              ((&&lux/analyse-apply (partial analyse-ast eval! compile-module compile-token) exo-type meta =fn ?args) state*))
-
-          [_]
-          ((analyse-basic-ast (partial analyse-ast eval! compile-module compile-token) eval! compile-module compile-token exo-type token) state)))
-      
-      [_]
-      (analyse-basic-ast (partial analyse-ast eval! compile-module compile-token) eval! compile-module compile-token exo-type token))))
+  (&/with-cursor (aget token 1 0)
+    (&/with-expected-type exo-type
+      (matchv ::M/objects [token]
+        [["lux;Meta" [meta ["lux;FormS" ["lux;Cons" [["lux;Meta" [_ ["lux;TagS" ?ident]]] ?values]]]]]]
+        (&&lux/analyse-variant (partial analyse-ast eval! compile-module compile-token) exo-type ?ident ?values)
+        
+        [["lux;Meta" [meta ["lux;FormS" ["lux;Cons" [?fn ?args]]]]]]
+        (fn [state]
+          (matchv ::M/objects [((just-analyse (partial analyse-ast eval! compile-module compile-token) ?fn) state)
+                               ;; ((&type/with-var #(&&/analyse-1 (partial analyse-ast eval! compile-module) % ?fn)) state)
+                               ]
+            [["lux;Right" [state* =fn]]]
+            (do ;; (prn 'GOT_FUN (&/show-ast ?fn) (&/show-ast token) (aget =fn 0 0) (aget =fn 1 0))
+                ((&&lux/analyse-apply (partial analyse-ast eval! compile-module compile-token) exo-type meta =fn ?args) state*))
+
+            [_]
+            ((analyse-basic-ast (partial analyse-ast eval! compile-module compile-token) eval! compile-module compile-token exo-type token) state)))
+        
+        [_]
+        (analyse-basic-ast (partial analyse-ast eval! compile-module compile-token) eval! compile-module compile-token exo-type token)))))
 
 ;; [Resources]
 (defn analyse [eval! compile-module compile-token]
diff --git a/src/lux/base.clj b/src/lux/base.clj
index ef3c81041..85e8df4d1 100644
--- a/src/lux/base.clj
+++ b/src/lux/base.clj
@@ -31,14 +31,15 @@
 (def $WRITER 2)
 
 ;; Compiler
-(def $ENVS 0)
-(def $EVAL? 1)
-(def $EXPECTED 2)
-(def $HOST 3)
-(def $MODULES 4)
-(def $SEED 5)
-(def $SOURCE 6)
-(def $TYPES 7)
+(def $cursor 0)
+(def $ENVS 1)
+(def $EVAL? 2)
+(def $EXPECTED 3)
+(def $HOST 4)
+(def $MODULES 5)
+(def $SEED 6)
+(def $SOURCE 7)
+(def $TYPES 8)
 
 ;; [Exports]
 (def +name-separator+ ";")
@@ -487,7 +488,9 @@
      (V "lux;None" nil))))
 
 (defn init-state [_]
-  (R ;; "lux;envs"
+  (R ;; "lux;cursor"
+   (T "" -1 -1)
+   ;; "lux;envs"
    (|list)
    ;; "lux;eval?"
    false
@@ -628,6 +631,20 @@
         [_]
         output))))
 
+(defn with-cursor [cursor body]
+  "(All [a] (-> Cursor (Lux a)))"
+  (if (= "" (aget cursor 0))
+    body
+    (fn [state]
+      (let [output (body (set$ $cursor cursor state))]
+        (matchv ::M/objects [output]
+          [["lux;Right" [?state ?value]]]
+          (return* (set$ $cursor (get$ $cursor state) ?state)
+                   ?value)
+
+          [_]
+          output)))))
+
 (defn show-ast [ast]
   (matchv ::M/objects [ast]
     [["lux;Meta" [_ ["lux;BoolS" ?value]]]]
diff --git a/src/lux/type.clj b/src/lux/type.clj
index 18f618b43..e4117492c 100644
--- a/src/lux/type.clj
+++ b/src/lux/type.clj
@@ -179,6 +179,7 @@
                                            (&/T "lux;seed" Int)
                                            (&/T "lux;eval?" Bool)
                                            (&/T "lux;expected" Type)
+                                           (&/T "lux;cursor" Cursor)
                                            )))
                        $Void)))