Re: Download navigation UX

On Wed, Jul 8, 2020 at 4:16 PM Magnus Hagander <magnus(at)hagander(dot)net> wrote:

>
> They're in separate files because they are setting up event handlers
>> specific to each page. I don't know of a way to do that with a shared file
>> without jumping through some likely hacky and fragile hoops to allow the
>> code to figure out what page it's been called from - i.e. making sure that
>> certain DOM IDs are always unique across any pages the shared file is
>> called from, and testing for the existence of those IDs to figure out what
>> event handlers to setup at runtime.
>>
>
> We already do similar in forms.js, though I have to admit a lot less than
> I thought we were. I guess I'm getting it slightly confused with other
> repos.
>

That's a *lot* more generic though from what I can see.

> We *already* have the requirement to keep "certain DOM Ids" unique -- we
> use it for CSS. And I really don't see that as any bigger problem than
> keeping the filename of the JS file unique.
>

Do you have an example? I can't see any obvious ones. Ideally we should be
using classes for CSS imho, rather than IDs anyway imho (and we really
shouldn't be using IDs in a way that requires them to be unique across
pages that may well be unknown to the casual hacker - that would be a real
maintenance headache).

>
>
> Having the separate files is certainly an extra download and slightly less
>> cacheable (for a few bytes of code), but I think that's outweighed by the
>> additional complexity and code that having a single file would require.
>>
>
> It's really more the latency than anything else. I'm pretty strongly on
> the side of thinking the cost of that is higher than the small amount of
> complexity -- I really don't think it would be much. But no, I'm not
> strongly *enough* on that side to actually try to produce proper metrics to
> prove it :)
>

The code complexity isn't that much I grant you. We'd have to wrap
something like the following around each event listener setup:

var elem = document.getElementById("elementID");
if (elem) {
// setup listener
}

However the cognitive complexity for the maintainer/developer of ensuring
IDs are unique across different pages is *much* higher.

--
Dave Page
Blog: http://pgsnake.blogspot.com
Twitter: @pgsnake

EDB: http://www.enterprisedb.com