Re: The first five minutes ... a thought experiment (long)

...and Henry has reminded me there are limitations with the shell
script approach.  You have one primary input (stdin) and the remaining
inputs are all secondary.  Hence, the reason why we want XProc for
processing documents.

On Thu, Feb 20, 2014 at 10:29 AM, Alex Milowski <alex@milowski.com> wrote:
> On Mon, Feb 17, 2014 at 3:30 PM, Zearin (Tony) <zearin@gonk.net> wrote:
>> On Feb 17, 2014, at 8:40 AM, James Fuller <jim@webcomposite.com> wrote:
>>> I) People know and love pipelines and have a set of preconceptions 'in
>>> wetware', before they come to XProc, about how pipelines should work.
>>>
>>> II) XProc balances off many engineering choices to handle the vagaries
>>> of managing pipelines big and small; its not trivial dealing with
>>> pipelines that go beyond simple 'piping output from input' between
>>> steps.
>>
>> # Let's learn from mistakes.
>>
>> IMO, together these statements highlight one of the **greatest** mistakes XProc ever made.
>>
>>
>> ## Regarding I
>>
>> XProc promises "pipelines". People know and love "pipelines". It is reasonable, therefore, for people to assume that their existing skills with pipelines will be portable to XProc--at least in some appreciable way.
>>
>> That is not the case.
>>
>>
>> ## Regarding II
>>
>> I think it was a mistake for XProc v1 to attempt anything beyond "simple 'piping output from input'" pipelines. UNIX-based tools are nothing more than this, and people are still using them 30+ years after the fact.
>>
>> By taking on the task of managing more complex pipelines, XProc damned itself to a hell of complexity: complexity for the implementors, and complexity for the users.
>>
>
> This is a bit mistaken.
>
> The Language Technology Group at Edinburgh has been using Unix pipes
> for longer than XML has existed (they did SGML before) to process
> language using pipelines implemented as shell scripts that pipe
> between programs.  You can build complex pipelines where the data flow
> graph contains meets and joins just fine in Unix shell scripts.  XProc
> was influence by these early adopters of pipelines for markup
> languages and the power they found in being able to do more than
> simple pipelines.  These people (Henry Thompson and Richard Tobin)
> were on the original WG and Henry, of course, still is quite active.
>
> There is a long history here.
>
> Meanwhile, straight-through pipelines that are simple chains of steps
> are quite straight forward to specify in XProc.
>
> I'd love to see some concrete examples of where this fails.
> Certainly, in V2, we want to do a better job of making simple things
> simple.
>
> [1] http://www.ltg.ed.ac.uk/software
>
> --
> --Alex Milowski
> "The excellence of grammar as a guide is proportional to the paucity of the
> inflexions, i.e. to the degree of analysis effected by the language
> considered."
>
> Bertrand Russell in a footnote of Principles of Mathematics



-- 
--Alex Milowski
"The excellence of grammar as a guide is proportional to the paucity of the
inflexions, i.e. to the degree of analysis effected by the language
considered."

Bertrand Russell in a footnote of Principles of Mathematics

Received on Thursday, 20 February 2014 10:53:19 UTC