RE: COBOL compiler

["David Turetsky" <davidturetsky@earthlink.net>]

On Tue, 2003-08-26 at 13:29, David Turetsky wrote:
> 
> Yes, but how does that compare with similarly powerful features in
Perl?



> I *knew* someone would ask about the Programmable Extraction and
> Reporting Language...
> 
> Please don't think that I am implying that Perl or C are bad
languages.
> I certainly wouldn't write a logfile analyzer in COBOL.
> 
> For my knowledge, how would Perl sort the contents of a file,
> allowing the programmer to use a complex algorithm as an
> input filter, and then take the output stream, processing it
> 1 record at a time, without needing to write to and then read
> from temporary files with all of the extra SLOC that that entails?
> 
> One thing that I don't think that any of the "modern" languages
> do, without extra libraries and function calls, is BCD arithmatic.
> 
> Here's a simplistic example of how COBOL is specialized:
> Say we have 2 record definitions:
> 01  A-SMALL-REC.
>     05  FIRST-NAME         PIC X(15).
>     05  LAST-NAME          PIC X(15).
> 01  A-LARGE-REC.
>     05  HONORIFIC          PIC X(5).
>     05  FIRST-NAME         PIC X(15).
>     05  MIDDLE-I           PIC X.
>     05  LAST-NAME          PIC X(15).
>     05  MODIFIER           PIC X(5).
> 
> MOVE 'JOHN' TO A-SMALL-REC.FIRST-NAME.
> MOVE 'DOE' TO A-SMALL-REC.LAST-NAME.
> MOVE SPACES TO A-LARGE-REC.
> 
> MOVE CORRESPONDING A-SMALL-REC TO A-LARGE-REC.
> 
> Here, A-SMALL-REC.FIRST-NAME and A-SMALL-REC.LAST-NAME will be
> moved to the corresponding fields in A-LARGE-REC.
> In such a trivial example, so what?  If, however, there are many
> fields in A-SMALL-REC, then MOVE CORRESPONDING is a big coding
> time-saver, and ensures that if the records definitions ever
> change, the code will still work.
> 
> 

You may or may not be correct in your assessment, but I do not believe
the above example particularly supports that view

If the "MOVE CORRESPONDING..." is recurring, you would write a
subroutine. If not, it's a one-time task, facilitated by a good editor

use Class::Struct

struct SmallRec  => {
   first-name    => '$',
   last-name     => '$',
}

struct LargeRec  => {
   honorific     => '$',
   first-name    => '$',
   middle-i      => '$',
   last-name     => '$',
   modifier      => '$',
}

$ASR = SmallRec->new();
$ASR->first-name('John');
$ASR->last-name('Doe');

$ALR = LargeRec->new();
$ALR->first-name($ASR->first-name);
$ALR->last-name($ASR->last-name);

Seems like a one-to-one correspondence to me, never mind the compactness
and power of Perl

-- 
David