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

On Mon, Feb 17, 2014 at 3:30 PM, Zearin (Tony) <> wrote:
> On Feb 17, 2014, at 8:40 AM, James Fuller <> 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


--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

Bertrand Russell in a footnote of Principles of Mathematics

Received on Thursday, 20 February 2014 10:30:26 UTC