Re: Naming convention to identify functions with side effects

[Brian Drummond <brian_drummond@btconnect.com>]

On Mon, 29 Sep 2008 22:48:20 +0200, Georg Bauhaus
<see.reply.to@maps.futureapps.de> wrote:

>Dmitry A. Kazakov wrote:
>> On Mon, 29 Sep 2008 11:55:49 -0700 (PDT), Adam Beneschan wrote:
>
>>>    if Web_Page_Is_Loaded ("http://www.irvine.com") then...
>>>    if Load_Web_Page ("http://www.irvine.com") then...
>> 
>> I don't like either.
>
>Me neither.
>
>Some issues become more obvious in a concurrent setting
>perhaps,
>
>   Web_Page.Load ("http://www.irvine.com");
>
>   if Web_Page.Is_Loaded then...
>
>There needs to be a lock of some sort joining the two calls.
>Otherwise, the Web_Page object might have changed
>between the two calls, a logic error.

As someone relatively new to Ada, I have to ask, is there need for
anything more sophisticated than

   Web_Page.Load ("http://www.irvine.com", Loaded);
   if Loaded then...

which avoids side effects in functions, preserves the atomicity of the
operation and test, but allows the test result to be used later. 
(The web page may indeed change, but "Loaded" refers to the version
extant during the .Load call)

Its intent and operation are quite clear, and it's a common paradigm in
other languages.

Beyond being a little untidy, is there any reason for avoiding it? 

- Brian