Re: Lisp reader and #1=... abbreviations

>>>>> "Jared" == Jared C Davis <[email protected]> writes:

    Jared> Hi,

    Jared> I'm having trouble reading in files which use a lot of
    Jared> structure-sharing abbreviations.  For example, here is a typical file
    Jared> (490 KB) which has 18,000+ abbreviations.  Unfortunately, reading this
    Jared> (with "read") takes about 13 minutes in CMUCL 19d on my test machine.

18000 abbreviations seems like an uncommon situation.

    Jared> We had similar trouble with OpenMCL, and discovered that the reader
    Jared> was using an association list to manage the abbreviations.  By
    Jared> replacing this with a hash table, Gary Byers reports speeding up the
    Jared> process from about 13 minutes to 1.2 seconds.

    Jared> I wonder if it would be possible to speed this up on CMUCL also?

CMUCL uses an alist so it seems possible to replace this with a hash
table.  I assume the hash table would slow down somewhat the typical
case, though.  But I haven't tested this.

I'll look into this a bit and see what can be done.

Ray