Sometimes, when you have, essentially, a WS full situation, GNU APL just dies instead of giving a WS FULL error.
x←⍳100000000 x[10000]←445 y←x /home/blake/bin/apl: line 3: 7341 Done akt 7342 Killed | /usr/local/bin/apl "$@" blake@blake-vmlinux ~ $ apl x←⍳100000000 /home/blake/bin/apl: line 3: 7964 Done akt 7965 Killed | /usr/local/bin/apl "$@" blake@blake-vmlinux ~ $ apl x←⍳10000000 ⍴x 10000000 y←x x←⍳10000000 x←⍳100000000 WS FULL x←⍳100000000 ^ ^ )off blake@blake-vmlinux ~ $ apl x←⍳100000000 /home/blake/bin/apl: line 3: 7992 Done akt 7993 Killed | /usr/local/bin/apl "$@"