I think the tenor of this debate misses an important point. 'Tacit' is
not a simple yes-or-no.
Take an example. Suppose I have a filespec (like 'C:\xxx\*.txt') and I
want a list of filenames in order of modification date, but not
including directories.
A beginner might write
files =. 1!:0 filespec
attrs =. 4 {"1 files
notdir =. 'd' ~: 4 {"1 > attrs
pfiles =. notdir # files
names =. 0 {"1 pfiles
times =. 1 {"1 pfiles
namesinorder =. names /: times
With more experience, they would see some opportunities for using tacit
features:
pfiles =. (#~ 'd' ~: (4;4)&{::"1) files
namesinorder =. (0&{"1 /: 1&{"1) pfiles
As J feels more natural, they might write
namesinorder =. (0&{"1 /: 1&{"1) (#~ 'd' ~: (4;4)&{::"1) 1!:0 filespec
(with appropriate comments, of course). Somewhere along the line this
would fail on an empty directory and they would add a test for that:
namesinorder =. (0&{"1 /: 1&{"1) (#~ 'd' ~: (4;4)&{::"1)^:(*...@#) 1!:0
filespec
If parts of that are useful enough to get their own names, they would:
culling =: 1 : 'u#]'
fisdir =: 'd' = (4;4)&({::)"1
ifany =: ^:(*...@#@])
and the solution would be written
namesinorder =. (0&{"1 /: 1&{"1) -...@fisdir culling ifany 1!:0 filespec
Is it tacit? Is it explicit?
Henry Rich
On 11/21/2010 2:10 PM, Dan Bron wrote:
> Ian wrote:
>> If reading tacit expressions posed no significant problems
>> to anyone except dunces, then surely there would have been
>> no need for this work and it would not have been done?
>>
>> So doesn't this put Bj�rn's assertion beyond debate?
>
> If reading Icelandic posed no significant problems to anyone except dunces,
> then surely there would be no need for this work:
>
> http://members.multimania.co.uk/mareka/iceland/icelandic.html
>
> and it would not have been done? Don't pages like that put my assertion
> beyond debate?
>
> It just takes practice, guys.
>
> -Dan
>
>
>
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