ABAP_to_the_Future

A
Improving Code Readability
This now works the same as MOVE-CORRESPONDING, but it’s longer—so if the target
structure is already partially filled and you want to keep the values, then you
might as well not bother and should stick with MOVE-CORRESPONDING.
The most compact code of all is of cour se machine code, which reads like this:
A098E564C63E231A45C. If you write a program in this fashion, then it ends up
very short indeed, but of course nobody can understand what it means. This is
why we have high-level languages like ABAP, which read like English and then
get compiled into a form the computer can understand but humans cannot. ABAP
has often been attacked for being very verbose when compared to other languages—for
example, ADD 1 TO ld_number., as opposed to Number++, which a lot
of experts seem to think is better. On the other side of the fence, academics such
as Donald Knuth have aimed for literate programming, in which the program is
supposed to read like a novel or a newspaper.
In essence, the benefit of “verbose” lang uage such as we have been used to in
ABAP is that the more like English it is, the easier it is to understand and thus to
change without breaking something. Contrariwise, as Tweedledum would say,
the benefit of the shorthand statements being introduced in ABAP 7.4 is to enable
you to achieve programming tasks in fewer lines of code, thus boosting productivity;
also, you can see more of the prog ram at once, so you don’t have to page
up and down so often.
Are these benefits mutually exclusive? Can you have the positive aspects of each
approach all at once—that is, have your cake and eat it too?
A.2 The What vs. the How
I think that we can, and the reason is thatthere are two things that we describe in
a program, each for different audiences.
When you’re tasked with adding some functionality or fixing a bug in someone
else’s program, a program you’ve never seen before, clearly the first thing you
need to understand is what it is doing (either what it is trying and failing to do or
what it needs to do in addition to what it currently does).
This “what I am doing” information needs to be in plain English so that you can
grasp it in a hurry. Programmers don’t read written documentation in Word documents
and the like—no one who works in IT does—so the information has to be
in the code.
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