On Sat, 08 Aug 2009, Sherlock Ric wrote:
> > From: Raul Miller
> > 
> > If it matters, the "official" definition of tacit:seems to be:
> > 
> > http://www.jsoftware.com/help/dictionary/intro.htm
> > 
> >   "...functional or tacit programming that requires no explicit
> >     mention of the arguments of a function (program) being
> >     defined, and the use of assignment to assign names to
> >     functions..."
> > 
> > The dictionary also mentions that 13 : may be used to create
> > tacit verbs.
> > 
> > (Essays can provide very good and useful material but usually
> > the dictionary will trump them.)
> > 
> > [That said, bill lam has already answered and explained what
> > he really means, and my post, here, was inspired by some
> > points raised in past threads.]
> 
> After reading Bill's post I found myself grappling in my own mind with what 
> was a tacit expression and what wasn't, which was why I started/renamed this 
> thread. I think Dan's post does a pretty good job of describing sorts of 
> ideas I was/am trying to reconcile. The dictionary description (I'm not sure 
> if it is really a definition?) didn't really clear things up for me.
> 
> If I write a "top level sentence" in the session manager
>   +/ 4 5 6
> Is it tacit or explicit? Is my sentence a) defining a function, b) executing 
> a function, or c) both?
> I'm thinking c), and given that the arguments are given but not explicitly 
> referred to, I'd also suggest that this is a tacit expression?
> 
> What about:
>    +/ *: 4 5 6
> How is this described? Is a function being defined? (maybe, but I'm not 
> sure!) If so, there doesn't seem to be any explicit reference to the 
> arguments - so is it therefore tacit?
> 

I'll take Raul's quotation to be official. It refers to a style of
programming by defining a series of names with other names without
explicit arguments in its reasoning.

take the example of standard deviation (not sure correct or not).

sum=: +/
mean=: sum % #
deviation=: sum - mean
meansquare=: *:@deviation % #
stddev=: %:@meansquare

certainly it is not about mechanically replacing x or y with [ and ]
because x or y never appeared in the first place.

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