Typical explicit adverbs produce the result of a sentence where the
argument replaces its corresponding parameter (usually u). In that sense,
an adverb is similar to a macro but there are other possibilities; for
instance, the adverb t1,
t1=. ([ , (<'@:') , ])/o |. o (('';1)&{::)hg
u0`u1`u2 t1
u2@:u1@:u0
u0`u1`u2`u3`u4 t1
u4@:u3@:u2@:u1@:u0
(Try to write t1 explicitly, macro-style.)
The difference between explicit and tacit adverbs is the same difference
between explicit and tacit verbs. They can produce the same results but
one relies on parameters (named arguments) whereas the other does not,
'y + 1 % (1 + y)' (verb :)
3 : 'y + 1 % (1 + y)'
'y + 1 % (1 + y)' (verb :) 5
5.16667
(] + 1 % (1 + ]))
] + 1 % 1 + ]
(] + 1 % (1 + ])) 5
5.16667
On Tue, Oct 24, 2017 at 4:40 AM, Erling Hellenäs <[email protected]>
wrote:
> See comments below:
>
>
> Den 2017-10-24 kl. 07:14, skrev Jose Mario Quintana:
>
>> EH> Hi all!
>>
>> Hi
>>
>> EH> All user-written adverbs and conjunctions are something similar to the
>> EH> macros in assembler and C++?
>>
>> I am not familiar with modern macros but if macros have an arbitrary but
>> fixed number of parameters then the answer is: not necessarily.
>>
> I am not familiar with those either, but my assumption is that the text
> set in the parameters simply replaces the parameters in the macros.
>
> abrakadabra t0
> abrakadabra + 1 % 1 + abrakadabra
>
>>
>> EH> There are external interfaces. You could call C/C++ code for example.
>> I
>> EH> don't know if it is possible for tacit code. I guess not.
>>
>> Tacit code can load libraries (e.g., addons) and execute verbs defined in
>> those libraries which might, or might not, call C/C++ code. I am not sure
>> if my answer answers your question though. :)
>>
> If you can extend J with adverbs and conjunctions written in C/C++, you
> could possibly generate the source code, compile them, link them and call
> them. That would be very different from the current macro-like adverb and
> conjunction definitions, it seems.
>
>
>> EH> What you do is to generate programs? In runtime, when running tacit
>>
>> Tacit adverbs, in J and Jx and tacit conjunctions in Jx produce entities
>> (nouns, verbs, adverbs, and conjunctions); those entities (apart from
>> nouns) can be explicit or tacit but I prefer to keep everything tacit.
>> Explicit adverbs and conjunctions produce the same kind of entities and
>> those can be explicit or tacit, but you already know this since your
>> explicit AtTacit below produces tacit verbs.
>>
>> EH> code, there is only the same built in code? Except then for some added
>> EH> functionality in Jx? But using explicit code, you can read user input
>> EH> and generate programs? Like we used to do with Do(".) ? How would you
>> EH> compare the methods you have with this traditional method to generate
>> code?
>> EH>
>> EH> Here my tacit conjunction AtTacit, equivalent with @:
>> EH> AtTacit=: 2 : '[: u v'
>> EH>
>> EH> The tacit code that actually executes is the second line, as far as i
>> EH> understand. AtTacit only remains until I give it verb arguments, and
>> EH> that will always happen before the actual tacit code is even parsed,
>> as
>> EH> far as I understand.
>> EH>
>> EH> <AtTacit-
>> EH> [: < -
>> EH>
>> EH> Your t0 can be defined like this?
>> EH>
>> EH> t0=: 1 : 'u + 1 % 1 + u'
>> EH> u t0 t0
>> EH> (u + 1 % 1 + u) + 1 % 1 + u + 1 % 1 + u
>> EH>
>>
>> Sure, but t0 defined this way is not a tacit adverb,
>>
>> t0
>> 1 : 'u + 1 % 1 + u'
>>
>> in contrast (beware of line-wrapping),
>>
>> t0=. (] , (+`'') , (an 1) , (%`'') , (an 1) , (+`'') , ]) hg
>>
>> t0
>> (("_)(((`'')(&((] , (,<,'+') , (<(,'0');1) , (,<,'%') , (<(,'0');1) ,
>> (,<,'+') , ])@:(<@:((0;1;0)&({::)))@:[)))((`_)(`:6))))(`:6)
>>
>> is tacit (it does not have any named arguments; there are no names
>> whatsoever)
>>
>> v t0
>> v + 1 % 1 + v
>>
>> v t0 t0
>> (v + 1 % 1 + v) + 1 % 1 + v + 1 % 1 + v
>>
>> I used hg to show that, even playing by the book, current J tacit
>> adverbial
>> programming is complete but tacit conjunctional programming is absent. I
>> prefer to use its evil twin sibling adv (defined in the J Wicked Toolkit);
>> adv was the model for the Jx version of adv (_1?:0). I wrote the
>> compliant
>> version of hg because Dan Bron implied that the original version cheated
>> which it did and I am proud of that ;)
>>
>> By the way, I wonder where Dan is. I really miss his posts, I learned a
>> lot
>> from them.
>>
> The difference still is not clear to me. I think before the resulting
> tacit code actually executes you have to give it an argument, and what then
> actually executes is exactly the same.
> t0EH=: 1 : 'u + 1 % 1 + u'
> t0JMQ=. (] , (+`'') , (an 1) , (%`'') , (an 1) , (+`'') , ]) hg
> t0EH
> 1 : 'u + 1 % 1 + u'
> t0JMQ
> (("_)(((`'')(&((] , (,<,'+') , (<(,'0');1) , (,<,'%') , (<(,'0');1) ,
> (,<,'+') , ])@:(<@:((0;1;0)&({::)))@:[)))((`_)(`:6))))(`:6)
> +t0EH
> + + 1 % 1 + +
> +t0JMQ
> + + 1 % 1 + +
> That t0JMQ, when the available words are replaced, does not contain any
> words does not make it tacit, as far as I understand. It is a mixture of
> tacit and explicit code, but before it all executes as a tacit expression,
> the replacements must be made in what seems equivalent to a text string,
> which can then be parsed by `:6 to another new tacit expression.
> It seems you are in a way handling functions as data, the question is in
> what ways it is better than the macro-like adverbs and conjunctions and the
> parse string functionality we always had, even in IBM APL/1 1980.
>
>
>> EH> Now you use your o=: @: ?
>> EH>
>> EH> *:`(+/)`-`j.`(^ %:)t1 1 2 3
>> EH> 2.40034j16.7123
>> EH> (^ %:) o j. o - o (+/) o *: 1 2 3
>> EH> 2.40034j16.7123
>> EH>
>> EH> The tacit executed code is the same? So it is about saving keypresses
>> EH> and about visual impression?
>> EH>
>>
>> I like to use o instead of @: for the following reasons: it reminds me of
>> the mathematical symbol for function composition (g º f)(x) = g(f(x)); @:
>> distracts me; o is easier to write.
>>
>>
>> EH> I admire your work. I'm not critical. I just want to give you the
>> EH> opportunity to explain it.
>>
>> I appreciate your comment and your effort to understand it. However, I
>> must say that "my" work has been heavily influenced by several past and
>> present members of the forum; yet the cheating is all mine.
>>
> :)
>
>
>> EH>
>> EH> Cheers,
>> EH>
>> EH> Erling Hellenäs
>>
>>
>> On Sat, Oct 21, 2017 at 3:43 PM, Erling Hellenäs <
>> [email protected]>
>> wrote:
>>
>> Hi all!
>>>
>>> I don't understand the meaning of "tacit adverb". Before parsing of the
>>> actual tacit trains, all adverbs and conjunctions are tied to their
>>> arguments? What remains is a verb train to be parsed? A verb train which
>>> contains some built-in adverbs and conjunctions? These are tied to their
>>> arguments under the hood? Remains a verb train composed to a single verb
>>> which executes later?
>>> All user-written adverbs and conjunctions are something similar to the
>>> macros in assembler and C++?
>>> Some of the built-in adverbs and conjunctions are compiled code with verb
>>> arguments, I guess. There is no way I know of for users to add or define
>>> such compiled adverbs and conjunctions.
>>> There are external interfaces. You could call C/C++ code for example. I
>>> don't know if it is possible for tacit code. I guess not.
>>> What you do is to generate programs ? In runtime, when running tacit
>>> code,
>>> there is only the same built in code? Except then for some added
>>> functionality in Jx? But using explicit code, you can read user input and
>>> generate programs? Like we used to do with Do(".) ? How would you compare
>>> the methods you have with this traditional method to generate code?
>>>
>>> Here my tacit conjunction AtTacit, equivalent with @:
>>> AtTacit=: 2 : '[: u v'
>>>
>>> The tacit code that actually executes is the second line, as far as i
>>> understand. AtTacit only remains until I give it verb arguments, and that
>>> will always happen before the actual tacit code is even parsed, as far
>>> as I
>>> understand.
>>>
>>> <AtTacit-
>>> [: < -
>>>
>>> Your t0 can be defined like this?
>>>
>>> t0=: 1 : 'u + 1 % 1 + u'
>>> u t0 t0
>>> (u + 1 % 1 + u) + 1 % 1 + u + 1 % 1 + u
>>>
>>> About the verb train. I know earlier there was a performance penalty for
>>> writing -@:-@:-@:-@:- trains and you generated parenthesis, like this i
>>> think: (-@:(-@:(-@:(-@:-)))). I can understand that. However this is no
>>> longer necessary, since the performance difference is corrected. It was
>>> also always possible to write strawmans([: - [:- [: - ]).
>>> Now you use your o=: @: ?
>>>
>>> *:`(+/)`-`j.`(^ %:)t1 1 2 3
>>> 2.40034j16.7123
>>> (^ %:) o j. o - o (+/) o *: 1 2 3
>>> 2.40034j16.7123
>>>
>>> The tacit executed code is the same? So it is about saving keypresses and
>>> about visual impression?
>>>
>>> *:`(+/)`-`j.`(^ %:)t1
>>>
>>> (^ %:)@:j.@:-@:(+/)@:*:
>>>
>>> (^ %:)o j.o-o(+/)o*:
>>>
>>> (^ %:)@:j.@:-@:(+/)@:*:
>>>
>>>
>>> I admire your work. I'm not critical. I just want to give you the
>>> opportunity to explain it.
>>>
>>> Cheers,
>>>
>>> Erling Hellenäs
>>>
>>>
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