Thank you for your reply, Hans-Peter. Sorry for the delay; it took some time to dig out my old interpreters. APL2, APL+Win, and Dyalog come up with the answer I expect. I do not see why reassignment would retain the structure of the prior contents. Is your point of view based upon selective assignment? Inserting a comma in the left hand side gives the result you expect: (,3⊃var)←⊂⊃'Susan' 'Mary' 'Annalisa'.
IBM APL2 2.0 Service Level 14 var←0 0 0 ⋄ (1⊃var)←5 4 ⋄ (2⊃var)←3 4⍴⍳12 ⋄ (3⊃var)←⊃'Sue' 'Maria' 'Annalisa' ⋄ var ⋄ (3⊃var)←⊂⊃'Susan' 'Mary' 'Annalisa' ⋄ var 5 4 1 2 3 4 Sue 5 6 7 8 Maria 9 10 11 12 Annalisa 5 4 1 2 3 4 Susan 5 6 7 8 Mary 9 10 11 12 Annalisa Dyalog 18.2.45505 ⎕ml←3 ⋄ ⎕io←1 ⋄ var←0 0 0 ⋄ (1⊃var)←5 4 ⋄ (2⊃var)←3 4⍴⍳12 ⋄ (3⊃var)←⊃'Sue' 'Maria' 'Annalisa' ⋄ var ⋄ (3⊃var)←⊂⊃'Susan' 'Mary' 'Annalisa' ⋄ var 5 4 1 2 3 4 Sue 5 6 7 8 Maria 9 10 11 12 Annalisa 5 4 1 2 3 4 Susan 5 6 7 8 Mary 9 10 11 12 Annalisa APL+Win 4.0 var←0 0 0 ⋄ (1⊃var)←5 4 ⋄ (2⊃var)←3 4⍴⍳12 ⋄ (3⊃var)←⊃'Sue' 'Maria' 'Annalisa' ⋄ var ⋄ (3⊃var)←⊂⊃'Susan' 'Mary' 'Annalisa' ⋄ var 5 4 1 2 3 4 Sue 5 6 7 8 Maria 9 10 11 12 Annalisa 5 4 1 2 3 4 Susan 5 6 7 8 Mary 9 10 11 12 Annalisa On Sat, Mar 4, 2023, at 14:25, Hans-Peter Sorge wrote: > Hi, > > Works as expected > > ⊃'Sue' 'Maria' 'Annalisa' > is an array 3 by 8. > > ⊂⊃'Susan' 'Mary' 'Annalisa' > is an element (⊂) of a 3 by 8 array (⊃'Susan' 'Mary' 'Annalisa' ). > > Finally each element in ⊃'Sue' 'Maria' 'Annalisa' gets assigned an > array of ⊃'Susan' 'Mary' 'Annalisa' > > Greetings > Hans-Peter > > Am 04.03.23 um 16:53 schrieb Mr. Sunday: >> Hi, >> >> I have an issue with reassigning an element of a nested array. Here is an >> example. >> >> 14535:15a:~% apl --version >> BUILDTAG: >> --------- >> Project: GNU APL >> Version / SVN: 1.8 / SVN: 1651M >> Build Date: 2023-03-02 00:25:07 UTC >> Build OS: Darwin 21.6.0 x86_64 >> config.status: default ./configure options >> Archive SVN: 1621 >> >> >> var←0 0 0 ⋄ (1⊃var)←5 4 ⋄ (2⊃var)←3 4⍴⍳12 ⋄ (3⊃var)←⊃'Sue' 'Maria' >> 'Annalisa' ⋄ var ⋄ (3⊃var)←⊂⊃'Susan' 'Mary' 'Annalisa' ⋄ var >> ┌→────────────────────────────┐ >> │┌→──┐ ┌→─────────┐ ┌→───────┐│ >> ││5 4│ ↓1 2 3 4│ ↓Sue ││ >> │└───┘ │5 6 7 8│ │Maria ││ >> │ │9 10 11 12│ │Annalisa││ >> │ └──────────┘ └────────┘│ >> └ϵ────────────────────────────┘ >> ┌→───────────────────────────────────────────────────────────────────────────────────────────────────────────┐ >> │┌→──┐ ┌→─────────┐ >> ┌→──────────────────────────────────────────────────────────────────────────────────────┐│ >> ││5 4│ ↓1 2 3 4│ ↓┌→───────┐ ┌→───────┐ ┌→───────┐ ┌→───────┐ ┌→───────┐ >> ┌→───────┐ ┌→───────┐ ┌→───────┐││ >> │└───┘ │5 6 7 8│ │↓Susan │ ↓Susan │ ↓Susan │ ↓Susan │ ↓Susan │ >> ↓Susan │ ↓Susan │ ↓Susan │││ >> │ │9 10 11 12│ ││Mary │ │Mary │ │Mary │ │Mary │ │Mary │ >> │Mary │ │Mary │ │Mary │││ >> │ └──────────┘ ││Annalisa│ │Annalisa│ │Annalisa│ │Annalisa│ │Annalisa│ >> │Annalisa│ │Annalisa│ │Annalisa│││ >> │ │└────────┘ └────────┘ └────────┘ └────────┘ └────────┘ >> └────────┘ └────────┘ └────────┘││ >> │ │ >> ││ >> │ │┌→───────┐ ┌→───────┐ ┌→───────┐ ┌→───────┐ ┌→───────┐ >> ┌→───────┐ ┌→───────┐ ┌→───────┐││ >> │ │↓Susan │ ↓Susan │ ↓Susan │ ↓Susan │ ↓Susan │ >> ↓Susan │ ↓Susan │ ↓Susan │││ >> │ ││Mary │ │Mary │ │Mary │ │Mary │ │Mary │ >> │Mary │ │Mary │ │Mary │││ >> │ ││Annalisa│ │Annalisa│ │Annalisa│ │Annalisa│ │Annalisa│ >> │Annalisa│ │Annalisa│ │Annalisa│││ >> │ │└────────┘ └────────┘ └────────┘ └────────┘ └────────┘ >> └────────┘ └────────┘ └────────┘││ >> │ │ >> ││ >> │ │┌→───────┐ ┌→───────┐ ┌→───────┐ ┌→───────┐ ┌→───────┐ >> ┌→───────┐ ┌→───────┐ ┌→───────┐││ >> │ │↓Susan │ ↓Susan │ ↓Susan │ ↓Susan │ ↓Susan │ >> ↓Susan │ ↓Susan │ ↓Susan │││ >> │ ││Mary │ │Mary │ │Mary │ │Mary │ │Mary │ >> │Mary │ │Mary │ │Mary │││ >> │ ││Annalisa│ │Annalisa│ │Annalisa│ │Annalisa│ │Annalisa│ >> │Annalisa│ │Annalisa│ │Annalisa│││ >> │ │└────────┘ └────────┘ └────────┘ └────────┘ └────────┘ >> └────────┘ └────────┘ └────────┘││ >> │ >> └ϵ──────────────────────────────────────────────────────────────────────────────────────┘│ >> └ϵϵ──────────────────────────────────────────────────────────────────────────────────────────────────────────┘ >> >> -- Everyday is Sunday. >> -- -- Everyday is Sunday.