Re: [Oorexx-devel] A handy little utility I propose adding to the core classes.

[Rony G. F. <Ron...@wu...>]

Rick McGuire wrote:
> In the process of adding some more error checks to the DateTime
> prototype this morning, I decide I was really getting tired of looking
> up error numbers for different types of arguments.  I wrote the
> following little utility class which makes common types of argument
> validation a lot simpler.  Note this requires the most recent build,
> as it's issuing the new 88.nnn argument error messages.  Now it's one
> line for each argument check, and the arguments are flagged by name
> rather than position.
Looks very neat!

One little suggestion: all of these check methods mandate a "name"
argument in all cases, and one or more arguments which get checked. For
that reason I would suggest to expect the "name" argument in the
ArgUtil-methods to be the first argument, followed by the value to be
checked as the second argument (which - depending on the check - may be
followed by additional values which should get used in the checking).
[This sequence would then also match the sequence of arguments used in
the raise-stattement.]

---rony

> ::CLASS "ArgUtil" public
> ::METHOD validateNumber class
>   use strict arg number, name
>   if \number~dataType('Number') then do
>       raise syntax 88.902 array(name, number)
>   end
>
> -- Validates the argument is a number and is in range.  This gives the
> -- 907 message for all error conditions to be most specific.
> ::METHOD validateNumberRange class
>   use strict arg number, name, min, max
>   -- validate the numeric part first
>   if \number~dataType('Number') then do
>       raise syntax 88.907 array(name, number)
>   end
>   -- now validate it's within range
>   if number < min | number > max then do
>       raise syntax 88.907 array(name, min, max, number)
>   end
>
>
> -- Validates the argument is a whole number and is in range.  This
> gives the
> -- 907 message for all error conditions to be most specific.
> ::METHOD validateWholeRange class
>   use strict arg number, name, min, max
>   -- validate the numeric part first
>   if \number~dataType('Whole') then do
>       raise syntax 88.907 array(name, number)
>   end
>   -- now validate it's within range
>   if number < min | number > max then do
>       raise syntax 88.907 array(name, min, max, number)
>   end
>
> ::METHOD validateWhole class
>   use strict arg number, name
>   if \number~dataType('Whole') then do
>       raise syntax 88.903 array(name, number)
>   end
>
> -- Note, this uses the 904 message for both, which is most specific
> ::METHOD validateNonNegative class
>   use strict arg number, name
>   -- first validate whole number status
>   if \number~dataType('Whole') then do
>       raise syntax 88.904 array(name, number)
>   end
>   -- then check range status
>   if number < 0 then do
>       raise syntax 88.904 array(name, number)
>   end
>
> ::METHOD validatePositive class
>   use strict arg number, name
>   -- first validate whole number status
>   if \number~dataType('Whole') then do
>       raise syntax 88.905 array(name, number)
>   end
>   -- then check range status
>   if number <= 0 then do
>       raise syntax 88.905 array(name, number)
>   end
>
> -- validate a length parameter.  This is essentially the same
> -- as validateNonNegative, but a more specific message.
> ::METHOD validateLength class
>   use strict arg number, name
>   -- first validate whole number status
>   if \number~dataType('Whole') then do
>       raise syntax 88.911 array(name, number)
>   end
>   -- then check range status
>   if number < 0 then do
>       raise syntax 88.911 array(name, number)
>   end
>
> -- validate a position parameter.  This is essentially the same
> -- as validatePosition, but a more specific message.
> ::METHOD validatePosition class
>   use strict arg number, name
>   -- first validate whole number status
>   if \number~dataType('Whole') then do
>       raise syntax 88.912 array(name, number)
>   end
>   -- then check range status
>   if number <= 0 then do
>       raise syntax 88.912 array(name, number)
>   end
>
> -- validate that an argument is an instance of a specific class.
> ::METHOD validateClass class
>   use strict arg obj, class, name
>
>   if \obj~isa(class) then do
>       raise syntax 88.914 array(name, class~id)
>   end
>