[antlr-interest] "start of line" issue in lexer

[Michiel Vermandel]

Hi,

I need a lexer rule to skip comment in a part of code-text.

The rule should only be used if "rem" is at the start of the line or only 
preceeded by whitespaces and/or tabs.

so given this part of code:


rem setting a to 5
set a=5;
rem setting lvrem to a
set lvrem = a;


the first and the third line should be concidered as comment.
the fourth line should be left alone.

building a rule for the case in line 3 is quite easy because I can search 
for new line characters, but for the very first line that is not possible 
since there are no preceeding new line characters.

how do I have to handle this?

Thanks a lott!
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