Re: sed and perl - yuck [Was Re: Preprocessor functionality equivalent ideas needed]

[Martin Krischik <krischik@users.sourceforge.net>]

Waldek Hebisch wrote:

> Martin Krischik (krischik@users.sourceforge.net) wrote:
> : Ludovic Brenta wrote:
> 
> : > Another approach could be to simulate a preprocessor with sed or perl
> : > scripts.
> 
> : Did that, hated it and wrote AdaCL. If you rather use Ada then perl and
> : find find sed cumbersome you should look at AdaCL.
> 
> : If you disagree: Write a sed line which inserst "OS." bevore every
> : CD_Recorder -  but only if it is not allready there.
> 
> Well, if you have unused chars (say ';' and '#') the task is easy:
> 
> s/CD_Recorder/;CD_Recorder/g
> s/OS\.;/OS.#/
> s/;CD_Recorder/OS.CD_Recorder/g
> s/[;#]//g
> 
> If all chars are used one have to quote first:
> 
> s/./:&/g
> s/:C:D:_:R:e:c:o:r:d:e:r/;::C:D:_:R:e:c:o:r:d:e:r/g
> s/:O:S:\.;:/:O:S:.;#/g
> s/;::C:D:_:R:e:c:o:r:d:e:r/:O:S:.:C:D:_:R:e:c:o:r:d:e:r/g
> s/;#:/:/g
> s/.\(.\)/\1/g

> I have not put them on sigle line for readability. 

Cool. But you do prove my point: sed is to compicated. Isn't Ada a lot
easier to read then sed:

AdaCL.SAR.Filter.List.Append (
    C    => Filters,
    Elem => AdaCL.SAR.Filter.Insert.Text.New_Object (
        SearchString  => "AdaCL.Trace",
        InsertString  => "..  ",
        Search_At     => AdaCL.SAR.Filter.Insert.First,
        Insert_At     => AdaCL.SAR.Filter.Insert.Before));

To much to type? With use and rename you could reduce it to:

Append (Flt, IT.New_Object ("AdaCL.Trace", "..  ", First, Before));

But we are Ada programers so we don't do that, do we.

> The above is
> slightly off-topic, but I think it ilustrates nicely that a sequence
> of simple steps can give result looking quite different then a single
> step. In that spirit Ada discourages preprocessors (since complexity
> grows quite a lot).

Yes true. However, in OS dependen programming you might have package which
is 90% the same and differ in 10%.

Still, I might give some of the ideas here are thought and maybe I get rid
of gnatprep.

With Regards

Martin

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