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From: John McCabe <"john@nospam.mccabe.org.uk">
Newsgroups: comp.lang.ada
Subject: Re: Ada and "early return" - opinion/practice question
Date: Tue, 16 Mar 2021 08:24:49 -0000 (UTC)
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On 15/03/2021 17:31, Stephen Leake wrote:
>John McCabe <john@mccabe.org.uk> writes:
>
<..snip..>

>> For example, you have a C++ function (pseudo code sort of thing):
>>
>> <sometype> fn(<some parameters>)
>> {
>>     if (<some undesirable condition 1>)
>>     {
>>         return <something bad happened 1>;
>>     }
>>
>>     if (<some undesirable condition 2>)
>>     {
>>         return <something bad 2>;
>>     }
>>
>>     if (<some undesirable condition 3>)
>>     {
>>         return <something bad 3>;
>>     }
>>
>>     // Only get here if everything's good...
>>     <do some real stuff>
>>     return <something good>;
>> }
>>

<snip>

>I would tend to use an exception for "something bad", but that depends
>on the overall design.

Thinking back on this point, would you do it a style where you try to do
 what needs to be done then handle the exception when it fails? For example,
 in this style

begin
    <try to do a good thing>
exception
    when blah blah
end

Or do you mean, rather than return when the undesirable condition occurs, do
 something like:

if <some undesirable condition 1> then
    raise <some exception 1>
end if;

In other words, does each undesirable condition, when it occurs, throw a
 [potentially] different exception?

Thanks
John