[antlr-interest] pass state from parser to lexer

Bart Kiers bkiers at gmail.com
Tue Jul 3 05:22:33 PDT 2012

On Mon, Jul 2, 2012 at 9:30 PM, Scobie Smith (Insight Global) <
v-scobis at microsoft.com> wrote:

> Thanks. Yes, here is the form of a statement in the language, which
> otherwise is context-free:
> exec mode <delimiter><body><delimiter>
> Statements always start at the beginning of a new line.
> <delimiter> is a single character that marks off the <body> text. The
> start/end delims match. The user can choose any character to be the
> <delimiter>.
> The <body>, though, may be multiline and have whitespace. But it cannot
> have the <delimiter> character in it.

> Example:
> exec mode #Here is
> Some body text.
> #
You can match such a token like this:

BODY  : {input.LA(1) == delimiter}?=> . ({input.LA(1) != delimiter}?=> . )*
. ;

where 'delimiter' is a character you set while instantiating the lexer and
putting it in the members-section like this:

@lexer::members {
  private char delimiter = '#';

Note that in my suggestion above, the 'BODY' might not end with
'delimiter', but with an EOF instead. You will need to do an extra check at
the end of the rule, if necessary.



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