Browse Prior Art Database

Use of Nested Return Codes

IP.com Disclosure Number: IPCOM000108994D
Original Publication Date: 1992-Jul-01
Included in the Prior Art Database: 2005-Mar-23
Document File: 2 page(s) / 76K

Publishing Venue

IBM

Related People

Beaty, KA: AUTHOR [+2]

Abstract

This article deals with the problem of identifying parameter errors to the calling program or person, when the call contains nested parameters, i.e., sub-structures of parameters. It is especially applicable to the APL2* environment, where nested arrays are very common. However, its scope extends to any language environment that deals with data structures and arrays, even if the individual members are not nested.

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This is the abbreviated version, containing approximately 52% of the total text.

Use of Nested Return Codes

       This article deals with the problem of identifying
parameter errors to the calling program or person, when the call
contains nested parameters, i.e., sub-structures of parameters.  It
is especially applicable to the APL2* environment, where nested
arrays are very common.  However, its scope extends to any language
environment that deals with data structures and arrays, even if the
individual members are not nested.

      The present-day solutions fall in two categories.  The first of
these is the atomic solution.  A single return code will be generated
and passed back to the calling program, caused by the first error to
be encountered.  The return-code or its associated message may or may
not try to identify the place of error in the parameter string.

      The second category of solutions does not stop at the first
error encountered, but will attempt to find and list as many errors
as possible.  Each of these error conditions will generate a separate
return code that will be passed back to the caller.  Again, the point
of error is typically not specifically identified in these return
codes, but only through listing the value in error suitably imbedded
in an accompanying error message.

      To solve the problem of pin-pointing the errors in the
parameter lists, return not just a single (or multiple)
return-code(s), but a structure of return codes.  This structure of
return codes must match the parameter list as far as the structure
itself is concerned.  Thus, each element in the parameter list will
have a matching return code.  Returning the information in this form
allows us to describe not only multiple individual errors, but the
location of the...