[antlr-interest] Appropriate use of honey badger listeners

[Gavin Lambert]

At 17:39 12/01/2012, Kyle Ferrio wrote:
 >If all we care about is detecting changes, a significant
 >speedup is possible if the interface for a tree object (or
 >for listeners acting on trees?) includes a flag that gets
 >flipped by any operation which has the possibility of
 >changing the tree.  (N.B. Possibility, not guarantee.  A
 >guarantee would require the eval we're trying to avoid.)

The usual solution for that is a version number, initialised to 
zero and incremented on any operation that alters the tree.  Much 
safer than a flag. :)

-- 
Gavin Lambert, Mirality Systems
<http://www.mirality.co.nz/>
<http://lambert.geek.nz/>
----
Anyone who goes to a psychiatrist ought to have their head 
examined.

Few women admit their age.  Few men act theirs.