> 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?

However the Essay description of tacit would conclude that this sequence of J 
operations doesn't preserve its features when assigned to a name and is 
therefore not a tacit expression.

Perhaps Dan's more recent posts will provide the illumination I seek!

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