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21. Re: Suggestion: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 564)

Author: Italo Maia <italo.maia@...>

Date: Sat, 29 Feb 2020 15:41:54 +0100

correction, this is valid lua: (mktable -p (table, a, b, c, d, e, f, g, ...)).with = value oh well .-.

22. Re: Suggestion: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 561)

Author: Diego Nehab <diego@...>

Date: Fri, 6 Mar 2020 19:08:29 -0300

On Fri, Mar 6, 2020 at 18:19 Egor Skriptunoff <egor.skriptunoff@gmail.com> wrote: On Fri, Mar 6, 2020 at 6:16 PM Diego Nehab wrote: In other words, t[f()] is always a single-index access, even when f

23. Re: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 561)

Author: Francisco Olarte <folarte@...>

Date: Sun, 1 Mar 2020 19:22:28 +0100

Anton: No, it does not, it just returns undef: folarte@7of9:~$ perl -e '@x=(1); for(4..6) { print $x[$_]//"x"; } print " $#x $^V\n";' xxx 0 v5.28.1 ( For the uninitiated, this creates a list with a s

24. Re: Suggestion: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 560)

Author: "Soni \"They/Them\" L." <fakedme@...>

Date: Fri, 28 Feb 2020 22:12:14 -0300

    If I want to access the value of t[a][b][c][d][e]     I suggest that it would be more useful -- and more consistent --     if the     "Attempt to index a nil value" error is deprecated and, inste

25. Re: Suggestion: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 560)

Author: "Soni \"They/Them\" L." <fakedme@...>

Date: Fri, 28 Feb 2020 22:10:51 -0300

If I want to access the value of t[a][b][c][d][e] I suggest that it would be more useful -- and more consistent -- if the "Attempt to index a nil value" error is deprecated and, instead, the indexing

26. Re: Suggestion: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 560)

Author: Egor Skriptunoff <egor.skriptunoff@...>

Date: Sat, 29 Feb 2020 04:05:19 +0300

On Sat, Feb 29, 2020 at 12:59 AM Anton Jordaan wrote: If I want to access the value of t[a][b][c][d][e] I suggest that it would be more useful -- and more consistent -- if the "Attempt to index a nil

27. Re: Suggestion: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 558)

Author: Egor Skriptunoff <egor.skriptunoff@...>

Date: Mon, 2 Mar 2020 12:57:07 +0300

On Mon, Mar 2, 2020 at 2:22 AM Sean Conner wrote:                 local a,a = 1,2 print(a)         and it's the second declaration that survives (Lua 5.3).  Weirder,         in the following:        

28. Re: Suggestion: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 558)

Author: Sven Olsen <sven2718@...>

Date: Sat, 29 Feb 2020 12:35:12 -0800

29. Re: Suggestion: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 557)

Author: Diego Nehab <diego@...>

Date: Sat, 7 Mar 2020 02:34:05 -0300

We have t(i1, i2, ...) --> getmetatable(t).__call(t, i1, i2, ...) This is always called. We are considering something like t[i1, i2, ...] --> getmetatable(t).__index(t, i1, i2, ...) t[i1, i2, ...] =

30. Re: Suggestion: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 557)

Author: Coda Highland <chighland@...>

Date: Fri, 6 Mar 2020 21:16:55 -0600

On Fri, Mar 6, 2020 at 8:01 PM Diego Nehab <diego@impa.br> wrote: I see a couple of competing arguments here. (1) It may be better to treat t[i,j] as being equivalent to t[i] in the absence of __inde

31. Re: Suggestion: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 557)

Author: Egor Skriptunoff <egor.skriptunoff@...>

Date: Sat, 7 Mar 2020 01:56:29 +0300

On Sat, Mar 7, 2020 at 1:09 AM Diego Nehab wrote: On Fri, Mar 6, 2020 at 18:19 Egor Skriptunoff wrote: IMO, that would make the whole proposal almost useless. Do you think that accessing a multi-inde

32. Re: Suggestion: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 557)

Author: Egor Skriptunoff <egor.skriptunoff@...>

Date: Sat, 7 Mar 2020 00:18:37 +0300

On Fri, Mar 6, 2020 at 6:16 PM Diego Nehab wrote: In other words, t[f()] is always a single-index access, even when f() returns multiple values. IMO, that would make the whole proposal almost useless

33. Re: Suggestion: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 555)

Author: Roberto Ierusalimschy <roberto@...>

Date: Mon, 2 Mar 2020 11:02:17 -0300

Note that Lua does not index variables, it indexes values. For instance, in the expression 'f(x).k = 1', if 'f(x)' is nil, there is no variable to get the new table. -- Roberto

34. Re: Suggestion: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 552)

Author: Diego Nehab <diego@...>

Date: Fri, 6 Mar 2020 23:00:55 -0300

I see a couple of competing arguments here. (1) It may be better to treat t[i,j] as being equivalent to t[i] in the absence of __index/__newindex. Combined with the above discussion about multi-retur

35. Re: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 551)

Author: Anton Jordaan <anton.jordaan@...>

Date: Sun, 1 Mar 2020 17:27:45 +0200

Italo Maio wrote: Perl has auto-vivification and it creates way more problems than it solves. Also agree this should not be part of the language and the error when trying to index a null value is a g

36. Re: Suggestion: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 550)

Author: Egor Skriptunoff <egor.skriptunoff@...>

Date: Sun, 1 Mar 2020 09:42:31 +0300

On Sat, Feb 29, 2020 at 10:35 PM connor horman wrote: Many of these, excluding ?# don?t have sensible defaults with operator overloading (which we get from metatables). Overloaded operators should re

37. Re: Suggestion: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 548)

Author: Coda Highland <chighland@...>

Date: Sat, 7 Mar 2020 00:29:56 -0600

On Fri, Mar 6, 2020 at 11:34 PM Diego Nehab <diego@impa.br> wrote: I do see the potential issue with the way the methods are called. With my suggested behavior, it only comes up if you have mixed ass

38. Re: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 548)

Author: Philippe Verdy <verdyp@...>

Date: Tue, 3 Mar 2020 15:37:18 +0100

Le mar. 3 mars 2020 à 12:53, Anton Jordaan <anton.jordaan@sylvean.com> a écrit : This is completely false. The real meaning is in fact much like: local _ref; _ref = t[a]; _ref = _ref[b]; _ref = _ref[

39. Re: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 546)

Author: Coda Highland <chighland@...>

Date: Sun, 1 Mar 2020 15:27:36 -0600

Could you elaborate why this is a non-starter? I have seen a number of solutions (including solutions that use metatables to define dynamic arrays, which are useful only when assigning) and also offe

40. Re: Suggestion: Deprecate "Attempt to index a nil value" error; instead, return nil or create table (score: 539)

Author: Roberto Ierusalimschy <roberto@...>

Date: Sun, 8 Mar 2020 12:44:49 -0300

"absolutely useless" is very harsh, almost aggressive, without any visible reason. If you cannot see why that would be useful, you can ask (or just ignore the message), but please let us keep a mini