Still having Internet troubles.

Two notes:  First, the text associated with a lexeme does *NOT* have to be
its value, if you use the lexeme_read() method to read it.  That's how you
can do the Ruby Slippers, for example.

Second, the text is fixed, but you can change how you move around in it --
you don't have to read it in order.  That allows some of the same effects
of changing the text, althjough not all.

A major reason that the text is fixed, is for error messages.  An error
message has to report an error as occurring *somewhere* in the error
stream.  But if you provide your own lexeme values, error messages will be
the only place where the lexeme-text association makes a difference.

On Mon, Feb 9, 2015 at 8:49 PM, Ron Savage <[email protected]> wrote:

> On Tuesday, 10 February 2015 14:24:56 UTC+11, Thomas Weigert wrote:
>>
>> Thanks, Ron.
>>
>> I see how the Ruby Slippers can work if you know ahead of time what the
>> text will be that we need to insert into the input, so we can "secret it
>> away" before calling read. I guess I could get this to work by prescanning
>> the input for all the text strings, then putting them all into "Ruby
>> Slippers Shoeboxes" at the end of the input string and when hitting one of
>> these tokens doing the Ruby Slipper thing, just like  you did in
>> match.parentheses.02.pl
>>
>
> But that prescanning is just what we want Marpa to do! Hmmm. The 4 points
> in your first post are incredibly restrictive. I suggest you revisit that
> topic. For example, if they are all prefixed with #, then life is
> simple(r). If they all end with \n, then that helps too. I still think the
> only way to handle a lot of flexibility in such introns (to use DNA-style
> terminology) is to accept that you'll have to write the grammar for all
> such cases. We can help you simplify it, but ATM it seems far too vague (in
> the nicest possible way, of course :-) to work with.
>
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