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Unnecessary Else Clause. [message #159625]

Thu, 20 May 2004 09:11

Vince O'Sullivan

Messages: 25
Registered: July 2009

Junior Member

A statement such as the following:

if (condition)
return 1;
else
return 2;

can throw up the warning (if user preferences include the option):
"Statement unnecessarily nested within else clause. The corresponding
then clause doe not complete normally."

Whilst the first statement is true can someone point me to a source of
information that would confirm the second part - about the abnormal
completion?

Thanks,
Vince.

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Re: Unnecessary Else Clause. [message #159729 is a reply to message #159625]

Fri, 21 May 2004 00:59

Eclipse User

Originally posted by: skoehler-remove-for-no-spam.upb.de

Vince wrote:
> A statement such as the following:
>
> if (condition)
> return 1;
> else
> return 2;
>
> can throw up the warning (if user preferences include the option):
> "Statement unnecessarily nested within else clause. The corresponding
> then clause doe not complete normally."

It does just mean, that your code is equivalent to

if (condition)
return 1;

return 2;

> Whilst the first statement is true can someone point me to a source of
> information that would confirm the second part - about the abnormal
> completion?

Well, the code "return 1;" doesn't complete (normally), since the VM
will never reach any code behind the return-statement.

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Re: Unnecessary Else Clause. [message #159968 is a reply to message #159625]

Fri, 21 May 2004 21:05

Michael Greer

Messages: 6
Registered: July 2009

Junior Member

Vince wrote:
> A statement such as the following:
>
> if (condition)
> return 1;
> else
> return 2;
>
Probably not a good idea anyway: it is much clearer to have only one
return, at the end, and change the return value with if/else statements
along the way.

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Re: Unnecessary Else Clause. [message #159975 is a reply to message #159729]

Fri, 21 May 2004 21:39

Eclipse User

Originally posted by: smesh.openrules.com

Search for "Unnecessary else statement" in
http://download2.eclipse.org/downloads/drops/S-3.0M9-2004052 11200/eclipse-news-all-M9.html
- it's explained well enough.

--
Sam Mesh - http://openrules.com

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Re: Unnecessary Else Clause. [message #160117 is a reply to message #159968]

Sun, 23 May 2004 04:25

Eclipse User

Originally posted by: akiezun.cuthis.mit.edu.andthis

> Vince wrote:
> > A statement such as the following:
> >
> > if (condition)
> > return 1;
> > else
> > return 2;
> >
> Probably not a good idea anyway: it is much clearer to have only one
> return, at the end, and change the return value with if/else statements
> along the way.

you sure ?
that'd be really ugly and not clean at at all - the 2 returns in the code
above is _much_ better, imo
a.

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Re: Unnecessary Else Clause. [message #160700 is a reply to message #160117]

Tue, 25 May 2004 19:28

Philippe Mulet

Messages: 229
Registered: July 2009

Senior Member

There is no better style I think. Sometimes we write code which become more
and more complex, and in the end we don't realize that we nested code too
much. This warning is just here to provide a way to signal these. It is up
to you to figure how you want to handle these. In particular, this is why I
did tolerate the else-if scenario, which I believe is a standard pattern.

"adam kiezun" <akiezun@cuthis.mit.edu.andthis> wrote in message
news:c8p8hi$t2b$1@eclipse.org...
> > Vince wrote:
> > > A statement such as the following:
> > >
> > > if (condition)
> > > return 1;
> > > else
> > > return 2;
> > >
> > Probably not a good idea anyway: it is much clearer to have only one
> > return, at the end, and change the return value with if/else statements
> > along the way.
>
> you sure ?
> that'd be really ugly and not clean at at all - the 2 returns in the code
> above is _much_ better, imo
> a.
>
>

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Re: Unnecessary Else Clause. [message #160844 is a reply to message #159975]

Wed, 26 May 2004 08:30

Vince O'Sullivan

Messages: 25
Registered: July 2009

Junior Member

I see the reasoning and don't have a problem with it however I'm still not
sure what is meant by the explanation that the then clause never
"completes normally". What exactly is the abnormality that is being
implied? To me it just looks like a style issue.

Example of then clause not completing "normally":
if (condition)
return 1;
else
return 2;

Example of then clause completing "normally":
if (condition)
return 1;

return 2;

Sam Mesh wrote:
> Search for "Unnecessary else statement" in
>
http://download2.eclipse.org/downloads/drops/S-3.0M9-2004052 11200/eclipse-news-all-M9.html
> - it's explained well enough.

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Re: Unnecessary Else Clause. [message #160939 is a reply to message #160844]

Wed, 26 May 2004 12:53

Philippe Mulet

Messages: 229
Registered: July 2009

Senior Member

The wording is inspired from the JLSpec 2nd edition section 14.1.

"Vince" <vjosullivan@hotmail.com> wrote in message
news:c91kid$bqv$1@eclipse.org...
> I see the reasoning and don't have a problem with it however I'm still not
> sure what is meant by the explanation that the then clause never
> "completes normally". What exactly is the abnormality that is being
> implied? To me it just looks like a style issue.
>
> Example of then clause not completing "normally":
> if (condition)
> return 1;
> else
> return 2;
>
> Example of then clause completing "normally":
> if (condition)
> return 1;
>
> return 2;
>
>
> Sam Mesh wrote:
> > Search for "Unnecessary else statement" in
> >
>
http://download2.eclipse.org/downloads/drops/S-3.0M9-2004052 11200/eclipse-news-all-M9.html
> > - it's explained well enough.
>
>

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