Hi, I am newbie on APL, so I am not sure below is a bug or not :-)
v ← (1 2 3) (4 5 6) f ← {1+⍵} f (⊂ 1 0 1)/¨v SYNTAX ERROR f(⊂1 0 1)/¨v ^ ^ However, adding parentheses works: f((⊂1 0 1)/¨v) 2 4 5 7 But f is function, with APL's right-associative rule, it should no need parentheses for f. ( Tested with TryAPL.org without parentheses and work without error ) BTW. here is my version info: ~ $ apl -v BUILDTAG: --------- Project: GNU APL Version / SVN: 1.4 / 7887 Build Date: 2014-08-07 15:46:58 UTC Build OS: Linux 3.11.0-12-generic x86_64 config.status: Readline: 0x0603 Thanks, David