Re: IF..ELSEIF vs SELECT

[Luis Rodriguez <luisro58@xxxxxxxxx>]

In some of the programming languages I know CASE is a somewhat more
efficient instruction than IF/ELSEIF. I don't know if that would be the
case (not pun intended) with RPG. On a personal level I find it a more
elegant and cleaner construct

Regards,
Luis

Sent from my Moto G phone. Please excuse my brevity.

On Tue, Sep 10, 2019, 06:36 john erps <jacobus.erps@xxxxxxxxx> wrote:

> Hi,
>
> Could anybody shed some light on when to use IF..ELSEIF and SELECT.
>
> Seems to me that the semantics of SELECT is exactly the same as IF..ELSEIF.
> SELECT just takes one line more (the SELECT).
>
> In other languages such as Java or Javascript you have a CASE statement.
> Maybe the idea is like this CASE statement. However a "normal" CASE
> statement like this selects between different individiual values of a
> variable. However, each WHEN statement in a SELECT is a full loagical
> expression, hence just the same as IF..ELSEIF.
>
> I use select when i need to condition using one variable. For example:
> SELECT
> WHEN X = 1
> ...
> WHEN X = 2
> ...
> ENDSL
>
> However:
> SELECT(X)
> WHEN 1
> ...
> WHEN 2
> ...
> ENDSL
>
> Would be a much better syntax, which resembles the CASE statement.
>
> I suspect that initially it would be just like a CASE statement, but, IBM
> being IBM, and camels and committees.... it ends up as another way of
> writing IF...ELSEIF.
>
> So better to shun it, and, for simplicities sake, always use IF..ELSEIF. Or
> is there a good reason to use SELECT? E.g. to communicate that it is simply
> a choice between values like CASE?
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