From: Nathaniel Wesley Filardo <nwf@cs.jhu.edu>
Date: Mon, 1 Jul 2013 04:04:43 +0000 (-0400)
Subject: Soften exception messages a bit
X-Git-Url: https://hydra-www.ietfng.org/gitweb/?a=commitdiff_plain;h=672e880292041352f1ff9bace06cef488605ff04;p=dyna2

Soften exception messages a bit

Some infinitessimal part of github issue #32.
---

diff --git a/src/Dyna/Main/Driver.hs b/src/Dyna/Main/Driver.hs
index dddd174..93f028d 100644
--- a/src/Dyna/Main/Driver.hs
+++ b/src/Dyna/Main/Driver.hs
@@ -387,10 +387,13 @@ processFile fileName = bracket openOut hClose go
                        tus = nHide $ IUniv UShared
                        tf  = nHide IFree
 
-            cqPlans = map (\(fa,r,e) -> (fa,r,check e)) qPlans
+            cqPlans = map check qPlans
                        where
-                        check (Right p) = p
-                        check (Left  _) = dynacPanic $ "Backchaining planner failed"
+                        check (f,r,Right p) = (f,r,p)
+                        check (_,r,Left  _) = dynacUserErr $
+						  "Unable to plan backchaining for rule"
+						  <//> (prettySpanLoc (r_span r))
+						  <> dot
 
         in do
             -- Do this before forcing cInitializers, cuPlans, etc.,
@@ -440,7 +443,7 @@ processFile fileName = bracket openOut hClose go
   parse aggs = do
     pr <- T.parseFromFileEx (P.oneshotDynaParser aggs <* T.eof) fileName
     case pr of
-      TR.Failure td -> dynacUserANSIErr $ PPA.align ("Parser error" PPA.<$> td)
+      TR.Failure td -> dynacParseErr $ PPA.align td
       TR.Success rs -> return rs
 
 
@@ -464,10 +467,10 @@ main = catches (getArgs >>= main_)
   printerr x = pe x >> exitFailure
 
   pe (UserProgramError d) = do
-    PP.hPutDoc stderr (upeMsg <> line <> PP.indent 1 d)
+    PP.hPutDoc stderr (upeMsg <> line <> PP.indent 1 d <//> upePostfix)
     hPutStrLn stderr ""
-  pe (UserProgramANSIError d) = do
-    PPA.hPutDoc stderr (upeMsg <> PPA.line <> PPA.indent 1 d)
+  pe (UserProgramParseError d) = do
+    PPA.hPutDoc stderr (parseMsg <> PPA.line <> PPA.indent 1 d)
     hPutStrLn stderr ""
   pe (InvocationError d) = do
     PP.hPutDoc stderr ("Invocation error:" <> line <> PP.indent 1 d)
@@ -489,7 +492,13 @@ main = catches (getArgs >>= main_)
     hPutStrLn stderr ""
 
   upeMsg :: (IsString s) => s
-  upeMsg = "FATAL: Encountered error in input program:"
+  upeMsg = "Encountered error in input program:"
+
+  upePostfix :: Doc e
+  upePostfix =      "Everything was syntactically valid, but we could not"
+               <//> "see it through."
+
+  parseMsg = "Could not parse:"
 
   sorryMsg :: (IsString s) => s
   sorryMsg = "Terribly sorry, but you've hit an unsupported feature"
diff --git a/src/Dyna/Main/Exception.hs b/src/Dyna/Main/Exception.hs
index b39cc98..35687ef 100644
--- a/src/Dyna/Main/Exception.hs
+++ b/src/Dyna/Main/Exception.hs
@@ -24,8 +24,8 @@ data DynacException =
     -- | The user program contains an error
     UserProgramError (PP.Doc TP.Effect)
 
-    -- | Same as 'UserProgramError' but with ANSI documentation
-  | UserProgramANSIError PPA.Doc
+    -- | Parser errors get their own branch for convenience of printout
+  | UserProgramParseError PPA.Doc
 
     -- | Something went wrong when trying to understand arguments
   | InvocationError (PP.Doc TP.Effect)
@@ -55,8 +55,8 @@ dynacPanicStr = throw . Panic . PP.text
 
 -- | Throw an ANSI error; this is used inside the parser, primarily, due to
 -- trifecta's movement to the ANSI prettyprinter.
-dynacUserANSIErr :: PPA.Doc -> a
-dynacUserANSIErr = throw . UserProgramANSIError
+dynacParseErr :: PPA.Doc -> a
+dynacParseErr = throw . UserProgramParseError
 
 -- | A type-restricted version of 'throw'
 dynacThrow :: DynacException -> a
diff --git a/test/repl/aggregator-conflict.expect b/test/repl/aggregator-conflict.expect
index a571301..3cff8f9 100644
--- a/test/repl/aggregator-conflict.expect
+++ b/test/repl/aggregator-conflict.expect
@@ -1,9 +1,11 @@
 :- :- =============
 a := 1
 :- DynaCompilerError:
-FATAL: Encountered error in input program:
- Conflicting aggregators; rule /home/timv/.dyna/tmp/966093dc38b755a6f17b02774b5c656931163a3a.dyna:5:1-/home/timv/.dyna/tmp/966093dc38b755a6f17b02774b5c656931163a3a.dyna:5:3
+Encountered error in input program:
+ Conflicting aggregators; rule /home/timv/.dyna/tmp/31141/966093dc38b755a6f17b02774b5c656931163a3a.dyna:5:1-/home/timv/.dyna/tmp/31141/966093dc38b755a6f17b02774b5c656931163a3a.dyna:5:3
  uses '|=' for a/0 but I had been lead to expect '+='.
+Everything was syntactically valid, but we could not
+see it through.
 
 > new rule(s) were not added to program.