parser: Improve error message for unrecognized input file format. (#3285)

diff --git a/src/parser/antlr_input.cpp b/src/parser/antlr_input.cpp
index 77efff951c12114c868fd9d9034f030564e838c3..3157ab6e5aa0a241a579063f2cbc2c6a0bdd3ef9 100644 (file)
--- a/src/parser/antlr_input.cpp
+++ b/src/parser/antlr_input.cpp
@@ -262,8 +262,7 @@ AntlrInput* AntlrInput::newInput(InputLanguage lang, AntlrInputStream& inputStre
     else
     {
       std::stringstream ss;
-      ss << "internal error: unhandled language " << lang
-         << " in AntlrInput::newInput";
+      ss << "unable to detect input file format, try --lang ";
       throw InputStreamException(ss.str());
     }
   }