[REBOL] Re: Browsers ,vim Vs. Emacs etc....
From: greggirwin:mindspring at: 16-Mar-2002 11:31
Joel, et al
<< Since much data from mainframes, or obtained via OCR (from TSU/SSU
sources, of course! ;-), is in fixed-record layout, it would be
interesting to have a program that would attempt to infer "field"
positions and lengths by examining the content of the data. >>
Do you remember our "table parsing" discussion some time ago? This strikes
me as a very similar problem, but with some added rules that may make things
a little trickier.
I'm not a COBOL/CICS/Mainframe guy, but I have had to deal with their data
at times. Most recently, I wrote a copy-lib parser (pseudo parser is
probably more accurate) so I could extract the format of a record and
generate a VB class from it, which then understands how to convert data
to/from a fixed buffer, but provides a native object for use in VB authored
apps. Records come and go via TCP sockets.
I haven't seen any really good examples of dealing with fixed length data in
REBOL, but it should certainly be possible. Start with a good dialect on the
REBOL side. Given a copylib, you could generate code in the dialect, or
maybe just interpret the copylib directly. The biggest problems I ran into
were strange and ambiguous things in copylibs. If you wanted it to be
complete, it would have to cover a pretty wide range of possibilities, but
PARSE should be well up to the task.