On Mon, Aug 24, 2009 at 11:24 AM, Tim Starling<[email protected]> wrote:
> I'm afraid your thinking on this is going in precisely the opposite
> direction to mine. I think long lists of formal parameters make code
> almost impossible to read and nearly as difficult to write. It might
> take slightly longer to type
>
> Html::img( array( 'src' => $src, 'alt' => $alt ) );
>
> but at least you can read that, and write it, without having to look
> up the parameter order in the documentation, and without having to
> memorise the parameter orders for large numbers of similar functions.
>
> Unless a programmer uses a function regularly, recalling what order
> the parameters should be in will be a difficult task, requiring
> several seconds if it's possible at all.
>
> . . .
>
> It would be good if we could have some sort of consensus on this so
> that we don't end up converting each others' code.
I agree with pretty much everything you've said. I only wish PHP
supported named parameters like Python, since PHP's array syntax is
pretty ugly. I'll see about removing Html::input(), at least. I'm
not sure yet whether HTMLForm is a suitable replacement, since it has
essentially no comments and I haven't yet done enough experimentation
to figure out how it works . . .
> Before being gradually replaced by this starting in MW 1.14:
>
> function link( $target, $text = null, $customAttribs = array(), $query
> = array(), $options = array() )
>
> which is an unfortunate example of bad design from the outset, since
> there are 5 formal parameters, 4 of them optional, and a number of
> callers only override $options. Consider this:
>
> $sk->link( $target, null, array(), array(), array( 'known' ) );
>
> versus this:
>
> $sk->link( $target, array( 'known' => true ) );
>
> and tell me which one is easier to understand and type.
To be fair, $sk->knownLink( $target ) is easier to type than either
and no harder to understand, and that's what's used now for this
*specific* case. I agree that condensing the options is a good idea,
though -- it's rare that any caller uses all five parameters, but many
use at least two or three, and often not the first two or three.
Something like
$sk->link(
$this->mTitle,
array(
'text' => wfMsgHtml( 'markaspatrolledtext' ),
'query' => array( 'action' => 'markpatrolled', 'rcid' => $rcid ),
'known', 'noclasses'
)
)
isn't very pretty, but it's certainly much more readable. I can't
remember the order of the parameters myself, and I wrote them.
It's actually pretty easy in PHP to totally switch over the kind of
parameters that a function takes. In the case of link(), we could
collapse the last four arguments into an associative array, and use
func_get_args() to fall back to the old way if the second argument is
a non-array.
_______________________________________________
Wikitech-l mailing list
[email protected]
https://lists.wikimedia.org/mailman/listinfo/wikitech-l
