Transferring code between APL suppliers in APL2000

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Transferring code between APL suppliers in APL2000

Overview

This page shows how to transfer code in workspaces or component files and read them back. This can be used to take backups or go back to previous versions of the interpreter.

It can also be used to import/export code from/to other interpreters.

Methods

There are at least 2 ways to export/import code in APL2000:

1. Using variable record length EXTENDED files

This format produces a representation of just about everything in the workspace. Translation of code from other APLs is limited but possible. For example, code imported from another APL might use Quad functions unavailable in APL2000. It can often be translated to use the equivalent APL2000 functions.

2. Using fixed record length ATF files

This format produces a representation of each function and variable in the workspace. It cannot perform translation of code when importing code from other APLs.

Technique

EXTENDED files

This format was introduced to deal with the 5 major APLs of the time (1990s): Sharp APL, APL*PLUS, APLX (discontinued), APL2 and Dyalog APL. It lays the representation of each variable or function in the ws, system variables included, onto variable length records.

You need a special workspace to read in and write out the code. The workspace should be available here: XFRPC11.w3.

ATF files

This format was introduced by IBM many years ago and has been supported by many other vendors, APL2000 included. It basically lays the representation of each object in the ws, system variables included, onto a number of 80 chars wide records in a file with extension ATF.

Note that the ATF file should be regarded as a binary file, not text. For example, the line-ending convention must be <CR><LF> (something which is apt to get changed when e-mailing ATF files between Windows and Macintosh systems, unless care is taken)

The user commands ]IN and ]OUT are used to import and export code in ATF format. No other software needs to be used.

Examples

Let's assume we have a workspace containing the following:

      title←'Big Application'
      ⎕fx ⊃'r←avg v' 'r←(sum v)÷⍴,v'
avg
      ⎕fx ⊃'z←sum x' 'z←+/x'
sum
      mat←.01×?2 5⍴10000
      record←'Joe Blough' 19550209 (.22 .45 1.2 1.56)

      ∇l←list
[1]   l←l,⎕nc l←⎕nl 2 3 4 5
[2]   ∇
      list
avg    3
list   3
mat    2
record 2
sum    3
title  2

      )WSID myws

Using the EXTENDED format

To write the workspace to file, including ⎕IO, ⎕CT, ⎕PW and ⎕LX (assume the workspace used to do the transfer is in \apl\xfrpc) do

      )COPY  \apl\xfrpc
      ∆xfrto '\tmp\mycode'
* XFR version  3.11
10 objects transferred

To write specific items put them before the file name (here 'title' and 'mat'):

     'title mat'  ∆xfrto '\tmp\my2objs'
* XFR version  3.11
2 objects transferred

To read the workspace back:

      )LOAD \apl\xfrpc
saved...
      ∆xfrfrom '\tmp\mycode.xsw  /replace'  ⍝ note the XSW extension, necessary when importing APL2000 code
* XFR version 3.11
APX3.11 20100217 34458; WS=myws
10 objects defined
      list
avg    3
list   3
mat    2
record 2
sum    3
title  2

To read only some groups

      )load \apl\xfrpc
SAVED  ...
      ∆xfrfrom '\tmp\mycode.xpw  /obj=c'  ⍝ bring in only character variables (c) 
* XFR version  3.11
APX3.09 20100217 40418; WS=myws
* "⎕lx:C" not redefined
3 objects defined
      ⎕nl 2 
mat
record
title

⎕LX was not redefined because we did not add the /replace switch.

Component files can be transferred too.

      '\tmp\ft1' ⎕fcreate 10
      title ⎕fappend 10
1
      record  ⎕fappend 10
2
      mat ⎕fappend 10
3
      (1 3⍴0 ¯1) ⎕fstac 10
      ⎕fsize 10
1 4 3584 0 0
      ∆xfrto '\tmp\exf1   /file=10'
* XFR version  3.11
3 cpts transferred with Access Matrix
      ∆xfrfrom '\tmp\exf1.xpf   /file=\tmp\new1'
* XFR version  3.11
4 objects defined
      '\tmp\new1' ⎕fstie 11
      ⎕fsize 11
1 4 3584 0 0
      ⎕fread 11 1
Big Application
      mat≡⎕fread 11 3
1
      ⎕frdac 11
0 ¯1 0

For details see http://www.milinta.com/xfrpc.htm.

Using the ATF format

To write the workspace to file do the following

      ]OUT \tmp\mycode

You cannot write specific items, only the entire workspace.

To read the workspace back:

      ]IN    \tmp\mycode
      ⍴⎕nl 2 3 
6 6

CategoryApl2000