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LDB vs LOAD-BYTE



    Date: Monday, 20 December 1982  21:37-EST
    From: MOON at SCRC-TENEX
    In-reply-to: The message of 2 DEC 1982 0504-PST from JONL at PARC-MAXC
    . . .
    and that (LDB (BYTE n-bits position) word) is slightly preferable to the
    introduction of a new function LOAD-BYTE, and would generate precisely
    the same code in any reasonable VAX compiler.

An unreasonable compiler can too.  The NIL compiler can (and does).  We
have already broken with the #oPPSS format.  More complicated are dealing
with the differences of byte extraction from subsequencing.  Integers are
treated as if they have infinite length, normal sequences are not, and
this is where hair arises when attempting to inline code a byte-extract
on a fixnum.