The ⍺ and ⍵ notation was introduced in 1974 http://www.jsoftware.com/papers/DirectDef.htm . Forks were invented by Ken Iverson and Eugene McDonnell on the way back from the APL88 conference in Sydney, Australia http://keiapl.org/rhui/remember.htm#fork0 , first written up in APL89 http://www.jsoftware.com/papers/fork.htm, and first implemented in J in September 1989 http://www.jsoftware.com/papers/J1990.htm .
Forks were recently implemented in Dyalog APL. On Thu, May 17, 2018 at 12:35 PM, Don Guinn <[email protected]> wrote: > True. I didn't have access to that APL, but read about it. And I didn't > grok tacit at the time. I do remember that they used alpha and omega for > left and right like x and y in J. At least, that's how I remember it. > > On Thu, May 17, 2018 at 1:23 PM, Roger Hui <[email protected]> > wrote: > > > If it used alpha and omega then it's not tacit. Tacit means no explicit > > mention of the function arguments; the term "tacit" was invented in 1991 > > http://www.jsoftware.com/papers/TacitDefn.htm . Tacit definition was > > first > > used APL\360, way back in 1966, as in +/ , but it was not recognized as > > tacit. What made tacit fly were forks, first implemented in J in version > > 0.1. In fact, tacit defn was implemented in J long before explicit defn. > > > > > > > > On Thu, May 17, 2018 at 12:14 PM, Don Guinn <[email protected]> wrote: > > > > > Tacit came out first in APL. Used alpha and omega. First time I saw > +/÷# > > > and thought "What is that??" (Sorry. Couldn't find rho.) > > > > > > On Thu, May 17, 2018, 11:24 AM David Lambert <[email protected]> > > wrote: > > > > > > > "APL and J are conceptually similar. That is, one knowing one > language > > > can > > > > easily pick up the other. " > > > > Verbs and rank thinking are easily transferred. Tacit programming > was > > > new > > > > and difficult for me, having used APL, APL2, and a VAX-VMS APL from > > DEC. > > > > .QQ is quote quad, .BX is box, etceteras. > > > > ------------------------------------------------------------ > ---------- > > > > For information about J forums see http://www.jsoftware.com/ > forums.htm > > > ---------------------------------------------------------------------- > > > For information about J forums see http://www.jsoftware.com/forums.htm > > > > > ---------------------------------------------------------------------- > > For information about J forums see http://www.jsoftware.com/forums.htm > > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
