Dyalog Forums

Does any know what version of Dyalog APL introduced control structures?

Hi Paul

I'm reasonably sure* that the first control structures (:If/:Then/:Else, :Repeat/:Until) were introduced in v8.1 (released March 1997). They've been added to since then – I think that the most recent addition was :Disposable in v14.1 (released June 2015).

*Geoff had a look in the code base but I did find other references to control structures possibly being introduced in 1995, which would be v7.1)

Thanks. Fi

FYI, https://aplwiki.com/wiki/Dyalog_APL#Versions has a good amount of this type of information

Thanks all.

Interesting to see that dfns and control structures came along at almost the exact same time.

I have a copy of Dyalog 7.4.3 currently running at this very moment on an old laptop with control structures.

Version 7 and 8 were(as far as the syntax) the same, version 7 was for Windows 3.1 and 8 for Win 95.

I am sure my copy of Dyalog APL for DOS/386 (serial No. 000168)bought in Feb 1991, did not.

Note: According to Dyalog at 25, version 8.1 introduced :Trap

In 1995 John Scholes and Pete Donnelly visited SunGard Capital Markets in Philadelphia. In the meeting they were told that Dyalog would have to implement Control Structures and that they would have to be identical to APL*2000's (for SunGard to use Dyalog), following which Dyalog implemented the control structures. As an aside, SunGard never converted because Yaron Avitov was unhappy with the ODBC fucnctionality that was included with Dyalog.