Multi-valued values in maps - sequences vs arrays
Wednesday, 3 August 2022 · 4 messages
BD
Bridger Dyson-Smith3 Aug 2022 06:27 #
Hi all -
I would appreciate some help understanding how I might go about having a multi-valued array as the value of a map key, or if this is even possible; e.g.
map{ "key": [1,2,3,4,5] }
I've tried various combinations of
array:flatten and array:join, but things always wind up in a sequence. (Aside: this isn't a real problem, but I'm trying to force myself to get more comfortable working with arrays and maps and this seemed like a great exercise... :) My mistake!).
E.g.
map:merge( (1 to 5) ! map {'key': array:flatten(array { . }) },
map{"duplicates":"combine"}
),
(: returns map{"key":(1,2,3,4,5)} :)
map:merge(
(1 to 5) ! map {'key': array:join(array {.}) },
map{"duplicates":"combine"}
)(: returns map{"key":([1],[2],[3],[4],[5])} :)
Are sequences the result because a map is a function item?
Thanks for any clarity you can provide!
Best,
Bridger
MH
Martin Honnen3 Aug 2022 10:37 #
Quoted text · Bridger Dyson-Smith · 8 lines
Am 03.08.2022 um 04:27 schrieb Bridger Dyson-Smith: > > > I would appreciate some help understanding how I might go about having > a multi-valued array as the value of a map key, or if this is even > possible; e.g. > > map{ "key": [1,2,3,4,5] }
map { 'key' : array { 1 to 5 } }
Or have I missed the point?
AB
Andy Bunce3 Aug 2022 12:04 #
Hi Bridger,
Quoted text · Martin Honnen · 1 line
> is even possible; e.g. map{ "key": [1,2,3,4,5] }
Well that works fine for me, so yes.
For your other examples, I think the answer is that
map:merge with map{ "duplicates":"combine"} always generates value *sequences *on duplicate keys.
So, maybe, generate the array you want, then put it in the maplet $a:=(1 to 5)!array{.}=>array:join()
return map:entry("key",$a)/Andy
Quoted text · Martin Honnen · 18 lines
On Wed, 3 Aug 2022 at 09:37, Martin Honnen <martin.honnen at gmx.de> wrote: > > Am 03.08.2022 um 04:27 schrieb Bridger Dyson-Smith: > > > > > > I would appreciate some help understanding how I might go about having > > a multi-valued array as the value of a map key, or if this is even > > possible; e.g. > > > > map{ "key": [1,2,3,4,5] } > > > map { 'key' : array { 1 to 5 } } > > > Or have I missed the point? > >
BD
Bridger Dyson-Smith3 Aug 2022 18:47 #
Andy and Martin -
with apologies, I didn't express my problem very well! Martin, you're correct with your example
map { 'key': array { 1 to 5 } }
and that was part of my struggle; i.e. "It works this way but not that way
- what am I doing wrong?" Andy noticed the source of my dilemma: I a using map:merge#2, with map { "duplicates": "combine" } -- Andy, thank you for catching that. I was entirely too caught up in a different part of the documentation.
I'm creating these maps from loose text, where keys are word pairs and values are value* (0, 1, or many). I'll come back with a better example of my problem, although I think you've both given me food for thought.
Thank you both so much for your help!
Best,
BridgerQuoted text · Andy Bunce · 35 lines
On Wed, Aug 3, 2022 at 6:04 AM Andy Bunce <bunce.andy at gmail.com> wrote: > Hi Bridger, > > > is even possible; e.g. map{ "key": [1,2,3,4,5] } > Well that works fine for me, so yes. > > For your other examples, I think the answer is that map:merge with map{ > "duplicates":"combine"} always generates value *sequences *on duplicate > keys. > So, maybe, generate the array you want, then put it in the map > > let $a:=(1 to 5)!array{.}=>array:join() > return map:entry("key",$a) > > /Andy > > On Wed, 3 Aug 2022 at 09:37, Martin Honnen <martin.honnen at gmx.de> wrote: > >> >> Am 03.08.2022 um 04:27 schrieb Bridger Dyson-Smith: >> > >> > >> > I would appreciate some help understanding how I might go about having >> > a multi-valued array as the value of a map key, or if this is even >> > possible; e.g. >> > >> > map{ "key": [1,2,3,4,5] } >> >> >> map { 'key' : array { 1 to 5 } } >> >> >> Or have I missed the point? >> >>
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