I agree with you, but we can do better. Usually I'm against all perl5 error messages, but I believe that this case is different. I am sure that this is what most people attempt to do at some point. I also know for sure that this is what I did a couple of times when I was starting with Perl 6. I also remember many times people were asking this on the channel.
So here's what I think: * A FAQ entry can be added. I created a doc issue for this: https://github.com/perl6/doc/issues/1300 * I think that it will be possible to add a compile-time error if you do something like ｢‘foo’[2]｣. That is, if somebody attempts to index a string literal, then we know for sure that it is wrong (… or at least, the error message will do more good than harm). On 2017-05-08 09:26:53, c...@zoffix.com wrote: > On Mon, 10 Oct 2016 06:05:10 -0700, alex.jakime...@gmail.com wrote: > > Code: > > say “hello”[2] > > > > Result: > > Index out of range. Is: 2, should be in 0..0 > > in block <unit> at -e line 1 > > > > Actually thrown at: > > in block <unit> at -e line 1 > > > > > > > > IRC discussion starting here: > > https://irclog.perlgeek.de/perl6/2016-10-10#i_13370830 > > > I don't get why we throw in this case at all. We don't do it with any > of the Positionals: > > <Zoffix_> m: say $_[42] for 1..1, (1,), [1,], (1,).Seq > <camelia> rakudo-moar 60f898: OUTPUT: «NilNil(Any)Nil» > > Other than Blob and Uni, which I'd say also break the consistency: > > <Zoffix_> m: say "".NFD[1] > <camelia> rakudo-moar 60f898: OUTPUT: «Index out of range. Is: 1, > should be in 0..-1 in block <unit> at <tmp> line 1Actually thrown > at: in block <unit> at <tmp> line 1» > <Zoffix_> m: say Blob.new[1] > <camelia> rakudo-moar 60f898: OUTPUT: «Index out of range. Is: 1, > should be in 0..-1 in block <unit> at <tmp> line 1Actually thrown > at: in block <unit> at <tmp> line 1» > > The throwage breaks the "everything is a 1-item list" idiom, as I > can't safely do $x[1], because > it'll explode any time $x is not a non-Stringy Positional. I tried to > remove the throwage, but it's blocked by several 6.c tests. > > And regardless of that, I'm -1 on this ticket. Right now $x[1] throws > X::OutOfRange on non-Positionals (even though it shouldn't), but the > proposed fix for this ticket would see the possibility of yet another > exception in another special case being thrown, all for the sake that > *someone new to the language* *assumes* Perl 6 can index strings. IMO > such special casing will be a hassle to more normal Perl 6 users than > a helpful tip to new Perl 6 users. Just recall how often the Perl-5- > ism exceptions get thrown when writing normal Perl 6 code.
