Bug #16609: `#sample` not working with blocks properly

• Status: Closed
• Assignee: -
• Target version: -
• ruby -v: 2.7.0 / 2.6.5
• Backport: 2.5: UNKNOWN, 2.6: UNKNOWN, 2.7: UNKNOWN

[LukeH7789 (Luke Hill)]

This may be a bug, it may be an uncoded/partially working feature. Running #sample with a block doesn't complain or throw an error; The following code runs, but doesn't execute correctly.

a = [1, 2, 3, 4, 5, 6]
a.sample(&:even?) #=> 1 or 3 or 5 is **expected**
a.sample { |e| e.even? } #=> 1 or 3 or 5 is **expected**

But if you run the second snippet, you can get any number from 1 to 6. Here are a few runs:

a.sample
# => 3
a.sample(&:even?)
# => 1
a.sample(&:even?)
# => 2
a.sample(&:even?)
# => 6
a.sample(&:even?)
# => 3
a.sample(&:even?)
# => 2

[LukeH7789 (Luke Hill)]

• ruby -v changed from 2.7.0 to 2.7.0 / 2.6.5

[matz (Yukihiro Matsumoto)]

• Status changed from Open to Closed

#sample do not take blocks. They are just ignored. It's one of the limitations of Ruby language.

Matz.

[nobu (Nobuyoshi Nakada)]

• Subject changed from #select not working with blocks properly to `#sample` not working with blocks properly

[sawa (Tsuyoshi Sawada)]

• Description updated (diff)