Using a . like a string concatentor causes COBRA INTERNAL ERROR.

[nevdelap]

Not that I think . is or should be a string concatenator - my fingers have just been doing too much damn php. :P

class P
    def main
        print "a" . "b"

error: COBRA INTERNAL ERROR / InvalidCastException? / Cannot cast from source type to destination type.

(I assume CIEs are always bad and worthy of tickets.)

[hopscc]

Hmm I get a CIE/RequireException but it barfs all the same.
heres some lines of patch that trap that situation and throw a nicer message

Index: CobraParser.cobra
===================================================================
--- CobraParser.cobra	(revision 2409)
+++ CobraParser.cobra	(working copy)
@@ -2782,6 +2782,9 @@
 						right = .expression(prec)
 					if op == 'ASSIGN' and left inherits IdentifierExpr and (left to IdentifierExpr).name.startsWithNonLowerLetter
 						.recordError(ErrorMessages.localVariablesMustStartLowercase)			
+					if op == 'DOT' 
+						if  left inherits StringLit  or right inherits StringLit
+							.throwError('Use plus "+", not dot ".", for string concatenation')
 					left = BinaryOpExpr.make(opToken to !, op to !, left to !, right)
 			finally
 				.opStack.pop

[hopscc]

Is this a common enough eror to require a full blown patch (patch+relnote+new test)

[Chuck]

Yes, we'll improve this. But I'll probably cut another 2010-09-XX release, apply your patch for 226 which hits the parser and then do this.

[Charles]

Fixed in changeset:2725 and changeset:2726.