cleaned up error messages generated via exceptions

asteroid/globals.py

@@ -63,31 +63,33 @@ def __init__(self, value):
         self.value = value
 
     def __str__(self):
-        return(repr(self.value))
+        return(str(self.value))
 
 #########################################################################
 class PatternMatchFailed(Exception):
     def __init__(self, value):
         self.value = "pattern match failed: " + value
 
     def __str__(self):
-        return(repr(self.value))
+        return(self.value)
 
 #########################################################################
 class NonLinearPatternError(Exception):
     def __init__(self, value):
         self.value = "non-linear pattern error: " + value
 
     def __str__(self):
-        return(repr(self.value))
+        return(self.value)
+
 #########################################################################
 class ExpectationError(Exception):
     def __init__(self, found, expected):
         self.found_EOF = (found == 'EOF')
         self.value = "expected {} found {}.".format(str(expected), str(found))
 
     def __str__(self):
-        return(repr(self.value))
+        return(self.value)
+
 ##############################################################################################
 # *** Part of the Redundant Pattern Detector ***
 #

asteroid/interp.py

@@ -75,6 +75,9 @@ def interp(input_stream,
         if symtab_dump:
             state.symbol_table.dump()
 
+    # Note: all exceptions generated by Asteroid should go through the handler
+    #       for 'Exception' unless the exception needs special handling like
+    #       'ThrowValue' or 'ReturnValue' etc.
     except ThrowValue as throw_val:
         # handle exceptions using the standard Error constructor
         module, lineno = state.lineinfo
@@ -96,36 +99,12 @@ def interp(input_stream,
         if not exceptions:
             sys.exit(1)
 
-    except RedundantPatternFound as e:
-        print("Error:  {}".format(e))
-        # needed for REPL
-        if not exceptions:
-            sys.exit(1)
-
-    except NonLinearPatternError as e:
-        print("Error:  {}".format(e))
-        # needed for REPL
-        if not exceptions:
-            sys.exit(1)
-
     except  KeyboardInterrupt as e:
         print("Error: keyboard interrupt")
         # needed for REPL
         if not exceptions:
             sys.exit(1)
 
-    # Expectation Error is used by the REPL, so, like exceptions,
-    # we re throw it
-    except ExpectationError as e:
-        if exceptions:
-            raise e
-        else:
-            module, lineno = state.lineinfo
-            print("Error: {}: {}: {}".format(module, lineno, e.value))
-            # needed for REPL
-            if not exceptions:
-                sys.exit(1)
-
     except Exception as e:
         if exceptions: # rethrow the exception so that you can see the full backtrace
             if symtab_dump:
@@ -138,7 +117,7 @@ def interp(input_stream,
             if not exceptions:
                 sys.exit(1)
 
-    except  BaseException as e:
+    except BaseException as e:
         print("Error: {}".format(e))
         # needed for REPL
         if not exceptions:

asteroid/walk.py

@@ -503,7 +503,7 @@ def check_repeated_symbols( unifiers ):
 
         elif sym in symbols: # We have found a non-linear pattern
             raise NonLinearPatternError(
-            "multiple instances of {} found within a pattern.".format(sym))
+            "multiple instances of '{}' found within pattern.".format(sym))
 
         else: # Else we have never seen this before so we record it.
             symbols[sym] = term