Re: Return versus Side-Effect

From:

peter koch larsen <peter.koch.larsen@gmail.com>

Newsgroups:

comp.lang.c++.moderated

Date:

Sun, 30 Mar 2008 13:42:24 CST

Message-ID:

<9bdf9109-8bfe-4005-8c0f-d27cf940572d@m3g2000hsc.googlegroups.com>

On 30 Mar., 17:40, hdante <hda...@gmail.com> wrote:

On Mar 27, 10:08 am, jeungs...@gmail.com wrote:

I have a function that takes a single string in, does some
manipulation, then gives an output.

1.) I can write the function prototype like this:

void doManipulation( const std::string & input, std::string &
output ); // (uses side-effect to return ouput string)

(if you're not afraid of pointers) do this:

void doManipulation( const std::string & input, std::string *
output );

now the calls make the side-effect evident:

doManipulation(x, &y);

As I argued in another thread, the pointervalue is not evidence of
change.
More importantly: if there is doubt as to whether or not a function
changes its parameters, this is more an indication that the programmer
writing the call knows to little to call the function in the first
place.

/Peter

[snip]

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