[antlr-interest] Interactive interpreter and line continuation characters

[lars.vonwedel at bayertechnology.com]

Hello,

I am trying to build an interactive interpreter shell for an application. 
A simple approach is obviously to read a line from the command line and 
send it to the lexer/parser.  However, the input language permits line 
continuation by special characters. If a line ends with a ';' or ',' it is 
supposed to be continued on the next line. 

To make things worse, some valid statements can end with multiple ',' 
characters. In this case, a special statement termination character '!' is 
used(and can be followed by arbitrary input to be disregarded).

My current line of thinking is to send a line entered by the user to the 
lexer, let it skip anything beyond '!' and then look at the last token. If 
that is a ';' or ',' then obtain another line and concatenate the token 
streams before actually running the parser.

Are there any better ideas how to deal with this ?

Freundliche Grüße / Best Regards
Lars von Wedel
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