ruby - Array.reject!(&:empty?) removes non-blank object -

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i can't figure out why, when using reject!(&:empty?), non-empty objects removed.

example:

["example"].reject!(&:empty?)

returns nil. however, 

["example", ""].reject!(&:empty?)

returns ["example"], should.

why?

from documentation:

equivalent #delete_if, deleting elements self block evaluates true, but returns nil if no changes made.

if want use result of array (and less interested in changing array - use reject instead:

["example"].reject(&:empty?) # => ["example"] ["example", ""].reject(&:empty?) # => ["example"]

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