Re: string_to_array, array_to_string function without separator

On Fri, Mar 15, 2019 at 12:31:21PM -0400, Chapman Flack wrote:
> On 3/15/19 12:15 PM, Tom Lane wrote:
> > Chapman Flack <chap(at)anastigmatix(dot)net> writes:
> >> So the proposal seems roughly equivalent to making string_to_array's
> >> second parameter optional default null, and array_to_string's second
> >> parameter optional default ''.
> >
> > In that case why bother? It'll just create a cross-version compatibility
> > hazard for next-to-no keystroke savings. If the cases were so common
> > that they could be argued to be sane "default" behavior, I might feel
> > differently --- but if you were asked in a vacuum what the default
> > delimiters ought to be, I don't think you'd say "no delimiter".
>
> One could go further and argue that the non-optional arguments improve
> clarity: a reader seeing the explicit NULL or '' argument gets a strong
> clue what's intended, who in the optional-argument case might end up
> thinking "must go look up what this function's default delimiter is".

Going to look up the function's behavior would be much more fun if
there were comments on these functions explaining things. I'll draft
up a patch for some of that.

In a similar vein, I haven't been able to come up with hazards of
naming function parameters in some document-ish way. What did I miss?

Best,
David.
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
Phone: +1 415 235 3778

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