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

5 files changed, 79 insertions, 45 deletions

diff --git a/source/lux.lux b/source/lux.lux
index ced208d40..36a0997f4 100644
--- a/source/lux.lux
+++ b/source/lux.lux
@@ -270,7 +270,8 @@
 ##      #host         HostState
 ##      #seed         Int
 ##      #eval?        Bool
-##      #expected     Type))
+##      #expected     Type
+##      #cursor       Cursor))
 (_lux_def Compiler
   (#AppT [(#AllT [(#Some #Nil) "lux;Compiler" ""
                   (#RecordT (#Cons [["lux;source" Reader]
@@ -284,7 +285,8 @@
                                                                     (#Cons [["lux;seed" Int]
                                                                             (#Cons [["lux;eval?" Bool]
                                                                                     (#Cons [["lux;expected" Type]
-                                                                                            #Nil])])])])])])])]))])
+                                                                                            (#Cons [["lux;cursor" Cursor]
+                                                                                                    #Nil])])])])])])])])]))])
           Void]))
 (_lux_export Compiler)
 
@@ -1316,7 +1318,8 @@
   (_lux_case state
     {#source source #modules modules
      #envs   envs   #types   types   #host     host
-     #seed   seed   #eval?   eval?   #expected expected}
+     #seed   seed   #eval?   eval?   #expected expected
+     #cursor cursor}
     (_lux_case (reverse envs)
       #Nil
       (#Left "Can't get the module name without a module!")
@@ -1355,7 +1358,8 @@
                    (_lux_case state
                      {#source source #modules modules
                       #envs   envs   #types   types   #host           host
-                      #seed   seed   #eval? eval? #expected expected}
+                      #seed   seed   #eval? eval? #expected expected
+                      #cursor cursor}
                      (#Right [state (find-macro' modules current-module module name)]))))))
 
 (def''' (list:join xs)
@@ -1912,10 +1916,12 @@
   (case state
     {#source source #modules modules
      #envs   envs   #types   types   #host           host
-     #seed   seed   #eval? eval? #expected expected}
+     #seed   seed   #eval? eval? #expected expected
+     #cursor cursor}
     (#Right {#source source #modules modules
              #envs   envs   #types   types   #host           host
-             #seed   (i+ 1 seed) #eval? eval? #expected expected}
+             #seed   (i+ 1 seed) #eval? eval? #expected expected
+             #cursor cursor}
             (symbol$ ["__gensym__" (->text seed)]))))
 
 (defmacro #export (sig tokens)
@@ -2187,7 +2193,8 @@
   (lambda [state]
     (let [{#source source #modules modules
            #envs   envs   #types   types   #host           host
-           #seed   seed   #eval? eval? #expected expected} state]
+           #seed   seed   #eval? eval? #expected expected
+           #cursor cursor} state]
       (#Right state expected))))
 
 (defmacro #export (struct tokens)
@@ -2403,7 +2410,8 @@
   (case state
     {#source source #modules modules
      #envs   envs   #types   types             #host  host
-     #seed   seed   #eval? eval? #expected expected}
+     #seed   seed   #eval? eval? #expected expected
+     #cursor cursor}
     (case (get module modules)
       (#Some =module)
       (#Right state true)
@@ -2417,7 +2425,8 @@
   (case state
     {#source source #modules modules
      #envs   envs   #types   types             #host  host
-     #seed   seed   #eval? eval? #expected expected}
+     #seed   seed   #eval? eval? #expected expected
+     #cursor cursor}
     (case (get module modules)
       (#Some =module)
       (let [to-alias (map (: (-> (, Text (, Bool (DefData' (-> (List AST) (StateE Compiler (List AST))))))
@@ -2600,7 +2609,8 @@
     (case state
       {#source source #modules modules
        #envs   envs   #types   types   #host           host
-       #seed   seed   #eval? eval? #expected expected}
+       #seed   seed   #eval? eval? #expected expected
+       #cursor cursor}
       (some (: (-> (Env Text (, LuxVar Type)) (Maybe Type))
                (lambda [env]
                  (case env
@@ -2634,7 +2644,8 @@
   (let [[v-prefix v-name] name
         {#source source #modules modules
          #envs   envs   #types   types   #host           host
-         #seed   seed   #eval? eval? #expected expected} state]
+         #seed   seed   #eval? eval? #expected expected
+         #cursor cursor} state]
     (case (get v-prefix modules)
       #None
       #None
@@ -2686,7 +2697,8 @@
           _
           (let [{#source source #modules modules
                  #envs   envs   #types   types   #host           host
-                 #seed   seed   #eval? eval? #expected expected} state]
+                 #seed   seed   #eval? eval? #expected expected
+                 #cursor cursor} state]
             (#Left ($ text:++ "Unknown var: " (ident->text name) "\n\n" (show-envs envs)))))))))
 
 (def (use-field field-name type)
diff --git a/source/lux/meta/lux.lux b/source/lux/meta/lux.lux
index 26513ed81..4d6c15bde 100644
--- a/source/lux/meta/lux.lux
+++ b/source/lux/meta/lux.lux
@@ -255,7 +255,8 @@
     (case state
       {#;source source #;modules modules
        #;envs   envs   #;types   types             #;host  host
-       #;seed   seed   #;eval? eval? #;expected expected}
+       #;seed   seed   #;eval? eval? #;expected expected
+       #;cursor cursor}
       (some (: (-> (Env Text (, LuxVar Type)) (Maybe Type))
                (lambda [env]
                  (case env
@@ -275,7 +276,8 @@
   (let [[v-prefix v-name] name
         {#;source source #;modules modules
          #;envs   envs   #;types   types   #;host           host
-         #;seed   seed   #;eval? eval? #;expected expected} state]
+         #;seed   seed   #;eval? eval? #;expected expected
+         #;cursor cursor} state]
     (case (get v-prefix modules)
       #;None
       #;None
@@ -310,6 +312,7 @@
              _
              (let [{#;source source #;modules      modules
                     #;envs   envs   #;types        types        #;host  host
-                    #;seed   seed   #;eval? eval? #;expected expected} state]
+                    #;seed   seed   #;eval? eval? #;expected expected
+                    #;cursor cursor} state]
                (#;Left ($ text:++ "Unknown var: " (ident->text name) "\n\n" (show-envs envs))))))))
     ))
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)))