[net.lang.ada] Ada errors with =>

franka@mmintl.UUCP (Frank Adams) (02/01/86)

John Goodenough has noted in his survey that the use of the => operator
tends to cause problems for those who are new to Ada.  This is accompanied
by a perception that it is used differently in different contexts.  I
believe this perception is incorrect; the use of the symbol is completely
uniform.  In general, its use in the form <name> => <value>.

Why, then, do people have so much trouble with it?  (And I had trouble with
it, too, when I first encountered it.)  The answer, I maintain, is because
the symbol looks like an arrow, and that arrow points in the wrong direction.

An arrow looks like an assignment, and we assign values to names, not vice
versa.

Since <= is not available, I think a direction neutral symbol, perhaps ==,
would have been a better choice.  It is perhaps too late to make this change
now; on the other hand, perhaps later versions of the language could support
it as an alternative.

Frank Adams                           ihpn4!philabs!pwa-b!mmintl!franka
Multimate International    52 Oakland Ave North    E. Hartford, CT 06108

cb@MITRE-BEDFORD.ARPA (Christopher Byrnes) (02/08/86)

  I'm not sure that the use of a `==' operator in place of the `=>' is
going to solve the problem.  As a "C" language programmer, I might
recognize the `==' operator as the logical equality operator.  I'm not sure
what other languages have used `==' for.  Ada's use of `=>' (for named
parameter association, etc.) is sufficiently different from what most other
computer languages provide that it deserves a "different" operator.  Once a
programmer gets use to the concept, they shouldn't mind which way the
"arrow" is pointing.
					Christopher Byrnes
					The MITRE Corporation
					Burlington Road
					M. S. A425
					Bedford, Mass. 01730

					cb@Mitre-Bedford.ARPA
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