Bug #5719

Hash::[] can't handle 100000+ args

Added by Nick Quaranto over 2 years ago. Updated over 1 year ago.

[ruby-core:41511]
Status:Assigned
Priority:Normal
Assignee:Koichi Sasada
Category:core
Target version:next minor
ruby -v:- Backport:

Description

I couldn't pin down an exact size for when/how this occurs, but I have code that was creating hashes just fine with Hash::[] with 300k+ arguments.

irb(main):056:0> (0...140000).map { |n| [:a, n] }.tap { |a| Hash[a] }.size
SystemStackError: stack level too deep
from /Users/qrush/.rbenv/versions/1.9.3-p0/lib/ruby/1.9.1/irb/workspace.rb:80
Maybe IRB bug!
irb(main):057:0> (0...130000).map { |n| [:a, n] }.tap { |a| Hash[
a] }.size
=> 130000

History

#1 Updated by John Glass over 2 years ago

I was able to duplicate this issue with the above code in 1.9.2-p290 It didn't matter if I ran it through IRB or from the command line.

#2 Updated by Gabriel Gironda over 2 years ago

It looks to be a variable argument length thing, not a Hash thing in particular.

https://gist.github.com/5037bf83d28c2c119c44

Edit: Not just variable argument length. Ruby just won't have any of your guff if you intend on passing any method a very large number of arguments.

https://gist.github.com/d259449ff7bedef92c2e

This is reasonable, I think.

#3 Updated by Yukihiro Matsumoto over 2 years ago

  • ruby -v changed from 1.9.3-p0 to -

Hi,

In message "Re: [ruby-trunk - Bug #5719][Open] Hash::[] can't handle 100000+ args"
on Wed, 7 Dec 2011 11:30:44 +0900, Nick Quaranto nick@quaran.to writes:

|I couldn't pin down an exact size for when/how this occurs, but I have code that was creating hashes just fine with Hash::[] with 300k+ arguments.

Unfortunately we are living in the very restricted real world. ;-)

                        matz.

#4 Updated by Bharanee Rathna over 2 years ago

i shall give you four hints: stack, heap, push, pop

ruby's behavior is expected.

you can pass Hash::[] an array instead i think.

Hash[[[:a, 1], [:b, 2]]] #=> {:a=>1, :b=>2}

#5 Updated by Martin Dürst over 2 years ago

This is related to http://redmine.ruby-lang.org/issues/982. In terms of what needs to be done, it may even be "the same" bug, although 982 is about a very long array literal, and this is about a very long array created by a splash. At http://redmine.ruby-lang.org/issues/982, Koichi Sasada said 「すみません,1.9.3 の後の課題とさせて下さい.」, i.e. "sorry, but let's deal with this after 1.9.3". So now may be a good time :-).

#6 Updated by Koichi Sasada about 2 years ago

  • Category set to core
  • Assignee set to Koichi Sasada
  • Target version set to 2.0.0

#7 Updated by Koichi Sasada about 2 years ago

(2011/12/07 14:26), Martin Dürst wrote:

This is related to http://redmine.ruby-lang.org/issues/982. In terms of what needs to be done, it may even be "the same" bug, although 982 is about a very long array literal, and this is about a very long array created by a splash. At http://redmine.ruby-lang.org/issues/982, Koichi Sasada said 「すみません,1.9.3 の後の課題とさせて下さい.」, i.e. "sorry, but let's deal with this after 1.9.3". So now may be a good time :-).

Thank you. It is correct. And there are no progress on it. Sorry.
Should we solve this issue as high priority?

--
// SASADA Koichi at atdot dot net

#8 Updated by Martin Dürst about 2 years ago

Hello Koichi,

On 2012/02/25 13:34, SASADA Koichi wrote:

(2011/12/07 14:26), Martin Dürst wrote:

This is related to http://redmine.ruby-lang.org/issues/982. In terms of what needs to be done, it may even be "the same" bug, although 982 is about a very long array literal, and this is about a very long array created by a splash. At http://redmine.ruby-lang.org/issues/982, Koichi Sasada said 「すみません,1.9.3 の後の課題とさせて下さい.」, i.e. "sorry, but let's deal with this after 1.9.3". So now may be a good time :-).

Thank you. It is correct.

Thanks for the confirmation.

And there are no progress on it. Sorry.
Should we solve this issue as high priority?

I'm not sure "high priority" is the right word. It's always possible to
work around it.

But it's highly annoying when somebody hits this issue. It's also highly
counterintuitive: Ruby deals with Arrays of any size automatically, but
then can't handle the same size in a literal.

So I very much think that 2.0 is a good point to get rid of this
problem. I'm not sure what's involved in fixing it, but if there's
something I can contribute, I'll be glad to help.

Regards, Martin.

#9 Updated by Shyouhei Urabe about 2 years ago

  • Status changed from Open to Assigned

#10 Updated by Koichi Sasada over 1 year ago

  • Target version changed from 2.0.0 to next minor

Also available in: Atom PDF