Tracing cases of failure got - openedge

Question

I'm trying to populate an integer variable from a character variable. If there is any error found I want to show the error message and trace all the possible cases for failure got.
//Defining variable
Define variable char_value as character no-undo initial "kk".
Define variable int_value as integer no-undo.
define variable ix as integer no-undo.
Assign int_value = integer(char_value) no-error.
IF ERROR-STATUS:ERROR OR ERROR-STATUS:NUM-MESSAGES > 0 THEN
DO:
MESSAGE ERROR-STATUS:NUM-MESSAGES
" errors occurred during conversion." SKIP
"Do you want to view them?"
VIEW-AS ALERT-BOX QUESTION BUTTONS YES-NO
UPDATE view-errs AS LOGICAL.
IF view-errs THEN
DO ix = 1 TO ERROR-STATUS:NUM-MESSAGES:
MESSAGE ERROR-
STATUS:GET-NUMBER(ix)
ERROR-STATUS:GET-
MESSAGE(ix).
END.
END.
There are two conditions which I want to know.
What char value I gave so that no. Of error returns will be more than 1.
How can I trace all the possible cases for failure got.

Answer 1

The built-in conversion routine does not do what you want it to do. So you will need to parse your input prior to attempting to convert it. Something like this:
function isDigit returns logical ( input d as character ):
if length( d ) = 1 then
return ( index( "0123456789", d ) > 0 ).
else
return no.
end.
procedure checkInteger:
define input parameter integerString as character no-undo.
define output parameter errorList as character no-undo.
define output parameter ok as logical no-undo.
define variable i as integer no-undo.
define variable n as integer no-undo.
define variable c as character no-undo.
ok = yes.
n = length( integerString ).
do i = 1 to n:
c = substring( integerString, i, 1 ).
if i = 1 and c = "-" then next.
if isDigit( c ) = no then
do:
ok = no.
errorList = errorList + substitute( "The character '&1' at offset &2 is not a valid integer value~n", c, i ).
end.
end.
errorList = trim( errorList, "~n" ). // remove the trailing newline (if any)
return.
end.
define variable ok as logical no-undo.
define variable errorList as character no-undo.
run checkInteger( "12x34y56z789", output errorList, output ok ).
if ok = yes then
message "string is a properly formed integer, go ahead and convert it".
else
message
"string was not correctly formed, do not try to convert it" skip
errorList
view-as alert-box information
.
Note #1 If the input contains unprintable characters the errorList string will display it literally and it will look kind of funny. You could, of course, encode them to be more readable. Doing so is left as an exercise. Or another question.
Note #2 This code makes no attempt to check that the string value will fit into an integer or an int64. That is also left as an exercise.

Answer 2

While you can make your parsing as complex as you like, I would just keep it simple and ensure the user is provided enough information, which in this case is the complete input value:
def var cc as char initial "kk".
def var ii as int.
ii = integer( cc ).
catch e as progress.lang.error:
message quoter( cc, "'" ) e:getMessage(1) view-as alert-box.
end catch.