General computer language, syntax question.

Joel Goldstick joel.goldstick at gmail.com
Mon Feb 29 09:38:50 EST 2016


On Mon, Feb 29, 2016 at 9:05 AM, <jonas.thornvall at gmail.com> wrote:

> Den måndag 29 februari 2016 kl. 14:57:04 UTC+1 skrev jonas.t... at gmail.com:
> > Den måndag 29 februari 2016 kl. 14:45:37 UTC+1 skrev
> jonas.t... at gmail.com:
> > > I have a problem programming uniform networks, "x nodes with y links"
> that turn out to be really hairy to solve for me and i feel i really lack
> the programming features
> > >
> > > "Actually i program in javascript" but the problem seem general for
> all programming languages including Pyhton.
> > >
> > > For a beautiful solution it would require "If in list/array return
> boolean" "If not in list/array return boolean".
> > >
> > > But there is no such feature Python nor Javascript, so instead i set
> boolean value "inlist" to false and loop thru, to see if it is already in
> list. If not it is added to list.
> > >
> > > So if the current node i generate links for is x and i try to generate
> a link to  node z, and z's links exhausted i will add it to exhausted list.
> > >
> > > And if there is node-x exhausted entries in list, well then script
> should break because it will lock into a cycle. The cyclic lockup is due to
> only a subset of the networks on the form (links*deep)+1=nodes is possible.
> > >
> > > So what i need is to know howto write "if list/array ***empty*** do
> {something}"
> > >
> > > I sure know howto check if an array have 1 element 2,3,4 but how do
> you check for empty.
> > >
> > > I think it is crazy that you can not do general comparissons of the
> type
> > > If in list/array
> > > If not in list/array
> > >
> > > But it is even more crazy that you can not check if list/array is
> empty, that is just madness.
> >
> > I mean for for example Javascript
> > if (typeof array[index] !== 'undefined' && array[index] !== null) {
> > or this one
> > if (array[index] != null) {
> >
> > I mean how do they come up with such convoluted syntax, do they pull it
> out of ass? Well one can always say it is needed because undefined not
> equal to null.
> >
> > But would not if (array[index]==empty) suffice and be alot clearer?
>
> Sorry but would not if (array==empty) suffice and be alot clearer?
> --
> https://mail.python.org/mailman/listinfo/python-list
>

You might have better luck on a javascript mailing list.  Not sure crazy,
madness, ass are descriptive to your problems

-- 
Joel Goldstick
http://joelgoldstick.com/ <http://joelgoldstick.com/stats/birthdays>
http://cc-baseballstats.info/


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