I ended up accidentally doing the equivalent of this in Ruby the other night:
a = *1..5 # => [1, 2, 3, 4, 5]
a << a
a # => [1, 2, 3, 4, 5, [...]]
a.last # => [1, 2, 3, 4, 5, [...]]
What is [...] and what can I do with it?
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Johan Svensson
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2I guess it's just a presentation markup, not valid syntax. Concerning recursive arrays - I've never used them. – John Dvorak Feb 15 '13 at 13:20
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1hah, haven't seen this before :) – Sergio Tulentsev Feb 15 '13 at 13:21
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4It's human for "omg so much output". Not sure what the question is, though, what " reference " are you referring to? – Dave Newton Feb 15 '13 at 13:22
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How did I manage to suggest _this_ as a duplicate? I meant to follow Anderw's suggestion. Sorry – John Dvorak Feb 15 '13 at 13:38
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-1 for sloppiness. `a` should not appear as `[1, 2, 3, 4, 5, [....]]`, it appears as `[1, 2, 3, 4, 5, [...]]`. – sawa Feb 15 '13 at 13:39
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It most certainly shows as `[....]` in irb (1.9.3) for me. I know this because that's where I cut'n'pasted it from. – Johan Svensson Feb 15 '13 at 13:41
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Sorry if that is the case. But on my irb 1.9.3, it shows as `[...]`. – sawa Feb 15 '13 at 13:44
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1Seems to be the wirble gem (for colorizing) that turns it from `[...]` to `[....]`. Editing the question since wirble isn't standard. – Johan Svensson Feb 15 '13 at 13:45
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Thanks for teaching me something there, +1. See comment by Andrew Marshall above to find the answer. – Boris Stitnicky Feb 15 '13 at 15:19
1 Answers
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It's just the way Array.inspect displays recursive arrays. The last Element of a is a itself. If a where displayed after 5, inspect would end up in an endless loop:
[1, 2, 3, 4, 5, [1, 2, 3, 4, 5, [1, 2, 3, 4, 5, [1, 2, 3, 4, 5, [...]]]]]
Torsten Robitzki
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