Newsgroups:   comp.lang.apl
Path: watmath!watserv2.uwaterloo.ca!torn!cs.utexas.edu!uunet!utcsri!geac!itcyyz!yrloc!intern
From:         pow@ipsa@ipsaint.ipsa.reuter.COM (Remote Addressee:)
Subject:      Keyed Files for J
Message-ID: <1992Dec21.223617.10162@yrloc.ipsa.reuter.COM>
Sender: intern@yrloc.ipsa.reuter.COM (Intern via QUADRAM)
Reply-To:     pow@ipsa@ipsaint.ipsa.reuter.COM (Remote Addressee:)
Organization: Reuters Information Services (Canada)
Date:         21 Dec 92 22:00:04 UT
Lines: 39


-----------Message forwarded from IPSA Mailbox-------------


no. 6846418 filed 21.13.59  mon 21 dec 1992
from pow@ipsa
to   uclapl
subj Keyed Files for J

@transferred from ipsa  no. 5456580 filed 21.13.48  mon 21 dec 1992

Below is a delete verb for keyed file access.

My access to InterNet is quite restricted. I can get messages forwarded
on to comp.lang.apl through the charity of Reuters. However, you cannot send
me personal mail by return. And unfortunately all such access is slated to
disappear shortly. (Emmett McLean: that's why pow@ipsa@ipsaint is an invalid
address.)
------------------
NB. key Delete <'filename'
NB.   Removes key from the list of keys.
NB.   Returns boolean (1=deleted, 0=not deleted).

m=.  < 'a=.ev y.,<0 512'
m=.m,< 'b=.ev y.,<0 1{0{a'
m=.m,< 'c=.ev y.,<0 1{1{a'
m=.m,< 'd=.-.b e. <x.'
m=.m,< 'b=.(,0{a) write y.,<rep <''b'' [ b=.d#b'
m=.m,< 'c=.(,1{a) write y.,<rep <''c'' [ c=.d#c'
m=.m,< 'a=.512{.rep<''a'' [ a=.2 3$b,c'
m=.m,< '0 e. d [ a iw y.,<0 512'
Delete =. '' : m


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being Reuters policy, or even as being approved by Reuters,
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