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I'm re-learning APL from the Gilman and Rose book. There are references to the i-beam functions to retrieve user information and the like, but I noticed they are not referenced in the APLX documentation which is more contemporary. Have they been superseded with other functions internal to APLX/APL2?

Paul Smietan
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You have an old version of Gilman and Rose. Mine (third edition) has moved on to APL2 Nested arrays.

The IBM I-Beam functionality has been superseded by Quad functions and variables. Eg: ⌶20 (Time of day in 60ths of a second) is now found in ⎕TS. ⌶22 is ⎕WA. ⌶27 is ⎕LC. Some mainframe values (eg ⌶23 user load ) have no equivalent.

Look in the APLX documentation for the Quad functions and variables.

Paul Houle
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    Thank you for the response! Yes, admittedly it's an old book, but I love to simplicity of their answers and the clear writing style. That said, I am now reading through the APLX documentation and will research the counterparts to i-beams. – Paul Smietan Jun 20 '17 at 16:44
  • Ibeam-23 was []UL (user load) on some timesharing systems, today user load would be either irrelevant or one. – Lobachevsky Jun 21 '17 at 08:15
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    There's more. Ibeam-26 was the first element of []LC, i.e. the current line. Ibeam-28 was the terminal type (?), irrelevant outside of a timesharing system. Ibeam-29 was the user number, on timesharing typically an integer, analogous to a logon id. There were some privileged ibeams which performs functions analogous to peek and poke. Ibeams are (sort of) making a comeback in Dyalog APL. – Lobachevsky Jun 21 '17 at 08:21
  • `5⌶` was delay in 1⁄300 of a second and has been superseded by `⎕DL` which takes its argument in seconds. – Adám Jul 12 '17 at 19:11
  • More historical trivia: In APL\360, index origin was set by the )ORIGIN command, or dynamically with 6⌶0,x. Similarly, no []RL, rather 6⌶1,x. )DIGITS, []PP, 6⌶2,x and finally )WIDTH, []PW, 6⌶3,x. Somewhere along the line there was a )FUZZ, []CT, 6⌶4,x (?). Clearly none of these could be localised. Delivered as locked functions in APL\360. All of these were removed from Sharp APL around May 1978. Otherwise useless info as these are not supported in any modern APL. See http://wotho.ethz.ch/mvt4apl-2.00/ for a trip down memory lane, these ibeams should work there. – Lobachevsky Aug 13 '17 at 12:43
  • Still interested? See http://www.softwarepreservation.org/projects/apl/Manuals/APL360UsersManuals – Lobachevsky Aug 13 '17 at 12:54