get stream position in the past

[Durand Jean-Damien]

Jeffrey,

Given a G1 level, a dot position and a rule ID, is it possible to get the corresponding stream position ?

For example, I am at G1 level 13, and I wonder what was the stream position of G1 level 10, because I found something of interest in it at rule id 2 and dot position 1.

Thanks, Jean-Damien.

[Jeffrey Kegler]

G1 "level"? Is this G1 location (Earley set)? -- jeffrey

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[Durand Jean-Damien]

Yes

[Jeffrey Kegler]

A stream span (that is, start and length) can be found as a function of G1 location.  If you are trying to conceptualize the location of the G1 parse in terms of a specific position in the G0 input, you'll most often think of the Earley set's location as being the end of that span (start + length).  I'll add a method to return the stream span for an arbitrary G1 location after I get the indexed release out today.  -- jeffrey

Durand Jean-Damien wrote: