- The compiler no longer complains about not catching RuntimeException and it's derivatives.

- Fixed a bug that cause the exception-handling scope of an outer function or method to be treaded as part of the exception-handling scope of an inner one.
- The return-type of ["jvm" "throw"] is now Bottom.
- Improved error messages coming from lux.base, by adding cursor data.

4 files changed, 68 insertions, 37 deletions

diff --git a/src/lux/analyser/host.clj b/src/lux/analyser/host.clj
index 729ffc4aa..a7b467564 100644
--- a/src/lux/analyser/host.clj
+++ b/src/lux/analyser/host.clj
@@ -23,22 +23,29 @@
   (:import (java.lang.reflect Type TypeVariable)))
 
 ;; [Utils]
-(defn ^:private ensure-catching [exceptions]
+(defn ^:private ensure-catching [exceptions*]
   "(-> (List Text) (Lux Null))"
   (|do [class-loader &/loader]
     (fn [state]
-      (let [exceptions (&/|map #(Class/forName % true class-loader) exceptions)
-            catching (->> state (&/get$ &/$host) (&/get$ &/$catching)
-                          (&/|map #(Class/forName % true class-loader)))]
+      (|let [exceptions (&/|map #(Class/forName % true class-loader) exceptions*)
+             catching (->> state
+                           (&/get$ &/$host)
+                           (&/get$ &/$catching)
+                           (&/|map #(Class/forName % true class-loader)))]
         (if-let [missing-ex (&/fold (fn [prev ^Class now]
                                       (or prev
-                                          (if (&/fold (fn [found? ^Class ex-catch]
-                                                        (or found?
-                                                            (.isAssignableFrom ex-catch now)))
-                                                      false
-                                                      catching)
-                                            nil
-                                            now)))
+                                          (cond (.isAssignableFrom java.lang.RuntimeException now)
+                                                nil
+
+                                                (&/fold (fn [found? ^Class ex-catch]
+                                                          (or found?
+                                                              (.isAssignableFrom ex-catch now)))
+                                                        false
+                                                        catching)
+                                                nil
+
+                                                :else
+                                                now)))
                                     nil
                                     exceptions)]
           ((&/fail-with-loc (str "[Analyser Error] Unhandled exception: " missing-ex))
@@ -314,10 +321,11 @@
                                ?ctor-args)
             =body (&/with-type-env full-env
                     (&&env/with-local &&/jvm-this class-type
-                      (with-catches (&/|map &host-generics/gclass->class-name ?exceptions)
-                        (&/fold (method-input-folder full-env)
-                                (&&/analyse-1 analyse output-type ?body)
-                                (&/|reverse ?inputs)))))]
+                      (&/with-no-catches
+                        (with-catches (&/|map &host-generics/gclass->class-name ?exceptions)
+                          (&/fold (method-input-folder full-env)
+                                  (&&/analyse-1 analyse output-type ?body)
+                                  (&/|reverse ?inputs))))))]
         (return (&/$ConstructorMethodAnalysis (&/T [=privacy-modifier ?strict ?anns ?gvars ?exceptions ?inputs =ctor-args =body]))))
       
       (&/$VirtualMethodSyntax ?name =privacy-modifier =final? ?strict ?anns ?gvars ?exceptions ?inputs ?output ?body)
@@ -326,10 +334,11 @@
             output-type (generic-class->type full-env ?output)
             =body (&/with-type-env full-env
                     (&&env/with-local &&/jvm-this class-type
-                      (with-catches (&/|map &host-generics/gclass->class-name ?exceptions)
-                        (&/fold (method-input-folder full-env)
-                                (&&/analyse-1 analyse output-type ?body)
-                                (&/|reverse ?inputs)))))]
+                      (&/with-no-catches
+                        (with-catches (&/|map &host-generics/gclass->class-name ?exceptions)
+                          (&/fold (method-input-folder full-env)
+                                  (&&/analyse-1 analyse output-type ?body)
+                                  (&/|reverse ?inputs))))))]
         (return (&/$VirtualMethodAnalysis (&/T [?name =privacy-modifier =final? ?strict ?anns ?gvars ?exceptions ?inputs ?output =body]))))
       
       (&/$OverridenMethodSyntax ?class-decl ?name ?strict ?anns ?gvars ?exceptions ?inputs ?output ?body)
@@ -339,10 +348,11 @@
             output-type (generic-class->type full-env ?output)
             =body (&/with-type-env full-env
                     (&&env/with-local &&/jvm-this class-type
-                      (with-catches (&/|map &host-generics/gclass->class-name ?exceptions)
-                        (&/fold (method-input-folder full-env)
-                                (&&/analyse-1 analyse output-type ?body)
-                                (&/|reverse ?inputs)))))]
+                      (&/with-no-catches
+                        (with-catches (&/|map &host-generics/gclass->class-name ?exceptions)
+                          (&/fold (method-input-folder full-env)
+                                  (&&/analyse-1 analyse output-type ?body)
+                                  (&/|reverse ?inputs))))))]
         (return (&/$OverridenMethodAnalysis (&/T [?class-decl ?name ?strict ?anns ?gvars ?exceptions ?inputs ?output =body]))))
 
       (&/$StaticMethodSyntax ?name =privacy-modifier ?strict ?anns ?gvars ?exceptions ?inputs ?output ?body)
@@ -350,10 +360,11 @@
             :let [full-env method-env]
             output-type (generic-class->type full-env ?output)
             =body (&/with-type-env full-env
-                    (with-catches (&/|map &host-generics/gclass->class-name ?exceptions)
-                      (&/fold (method-input-folder full-env)
-                              (&&/analyse-1 analyse output-type ?body)
-                              (&/|reverse ?inputs))))]
+                    (&/with-no-catches
+                      (with-catches (&/|map &host-generics/gclass->class-name ?exceptions)
+                        (&/fold (method-input-folder full-env)
+                                (&&/analyse-1 analyse output-type ?body)
+                                (&/|reverse ?inputs)))))]
         (return (&/$StaticMethodAnalysis (&/T [?name =privacy-modifier ?strict ?anns ?gvars ?exceptions ?inputs ?output =body]))))
 
       (&/$AbstractMethodSyntax ?name =privacy-modifier ?anns ?gvars ?exceptions ?inputs ?output)
@@ -675,9 +686,12 @@
 
 (defn ^:private analyse-jvm-throw [analyse exo-type ?values]
   (|do [:let [(&/$Cons ?ex (&/$Nil)) ?values]
-        =ex (&&/analyse-1 analyse (&/$HostT "java.lang.Throwable" &/$Nil) ?ex)
+        =ex (&&/analyse-1+ analyse ?ex)
+        _ (&type/check (&/$HostT "java.lang.Throwable" &/$Nil) (&&/expr-type* =ex))
+        [throw-class throw-params] (ensure-object (&&/expr-type* =ex))
+        _ (ensure-catching (&/|list throw-class))
         _cursor &/cursor
-        _ (&type/check exo-type &/$VoidT)]
+        _ (&type/check exo-type &type/Bottom)]
     (return (&/|list (&&/|meta exo-type _cursor
                                (&&/$proc (&/T ["jvm" "throw"]) (&/|list =ex) (&/|list)))))))
 
diff --git a/src/lux/analyser/lux.clj b/src/lux/analyser/lux.clj
index 0ce5c060a..6f8ccae57 100644
--- a/src/lux/analyser/lux.clj
+++ b/src/lux/analyser/lux.clj
@@ -399,8 +399,8 @@
                                     ((&/fail-with-loc error) state)))
                 module-name &/get-module-name
                 ;; :let [[r-prefix r-name] real-name
-                ;;       _ (when (or (= "defstruct" r-name)
-                ;;                   (= "struct" r-name)
+                ;;       _ (when (or (and (= "lux/data/maybe" r-prefix)
+                ;;                        (= "?" r-name))
                 ;;                   ;; (= "@type" r-name)
                 ;;                   )
                 ;;           (->> (&/|map &/show-ast macro-expansion)
@@ -559,7 +559,8 @@
     ))
 
 (defn analyse-lambda [analyse exo-type ?self ?arg ?body]
-  (|do [output (analyse-lambda** analyse exo-type ?self ?arg ?body)]
+  (|do [output (&/with-no-catches
+                 (analyse-lambda** analyse exo-type ?self ?arg ?body))]
     (return (&/|list output))))
 
 (defn analyse-def [analyse optimize eval! compile-def ?name ?value ?meta]
diff --git a/src/lux/base.clj b/src/lux/base.clj
index 48eb00469..2dc684144 100644
--- a/src/lux/base.clj
+++ b/src/lux/base.clj
@@ -756,6 +756,17 @@
         (|table)
         ])))
 
+(defn with-no-catches [body]
+  "(All [a] (-> (Lux a) (Lux a)))"
+  (fn [state]
+    (let [old-catching (->> state (get$ $host) (get$ $catching))]
+      (|case (body (update$ $host #(set$ $catching $Nil %) state))
+        ($Right state* output)
+        (return* (update$ $host #(set$ $catching old-catching %) state*) output)
+
+        ($Left msg)
+        (fail* msg)))))
+
 (defn default-compiler-info [mode]
   (T [;; compiler-name
       compiler-name
@@ -828,14 +839,14 @@
         (return* state datum)
 
         _
-        (fail* "Writer hasn't been set.")))))
+        ((fail-with-loc "Writer hasn't been set.") state)))))
 
 (def get-top-local-env
   (fn [state]
     (try (let [top (|head (get$ $envs state))]
            (return* state top))
       (catch Throwable _
-        (fail* "No local environment.")))))
+        ((fail-with-loc "No local environment.") state)))))
 
 (def gen-id
   (fn [state]
@@ -864,7 +875,7 @@
   (fn [state]
     (|case (|reverse (get$ $envs state))
       ($Nil)
-      (fail* "[Analyser Error] Can't get the module-name without a module.")
+      ((fail-with-loc "[Analyser Error] Can't get the module-name without a module.") state)
 
       ($Cons ?global _)
       (return* state (get$ $name ?global)))))
@@ -874,7 +885,7 @@
   (fn [state]
     (if-let [module (|get name (get$ $modules state))]
       (return* state module)
-      (fail* (str "Unknown module: " name)))))
+      ((fail-with-loc (str "Unknown module: " name)) state))))
 
 (def get-current-module
   "(Lux (Module Compiler))"
@@ -983,7 +994,7 @@
       (return* state unit-tag)
 
       ($Some _)
-      (fail* "[Error] All statements must be top-level forms."))))
+      ((fail-with-loc "[Error] All statements must be top-level forms.") state))))
 
 (def cursor
   ;; (Lux Cursor)
diff --git a/src/lux/type.clj b/src/lux/type.clj
index 295d7bfdb..4661b3166 100644
--- a/src/lux/type.clj
+++ b/src/lux/type.clj
@@ -34,6 +34,11 @@
 (def Text (&/$NamedT (&/T ["lux" "Text"]) (&/$HostT "java.lang.String" &/$Nil)))
 (def Ident (&/$NamedT (&/T ["lux" "Ident"]) (&/$ProdT Text Text)))
 
+(def Bottom
+  (&/$NamedT (&/T ["lux" "Bottom"])
+             (&/$UnivQ empty-env
+                       (&/$BoundT 1))))
+
 (def IO
   (&/$NamedT (&/T ["lux/codata" "IO"])
              (&/$UnivQ empty-env