method
flatten!
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flatten!(p1 = v1)
public
Flattens self in place.
Returns nil if no modifications were made (i.e., the array contains no subarrays.)
The optional level argument determines the level of recursion to flatten.
a = [ 1, 2, [3, [4, 5] ] ] a.flatten! #=> [1, 2, 3, 4, 5] a.flatten! #=> nil a #=> [1, 2, 3, 4, 5] a = [ 1, 2, [3, [4, 5] ] ] a.flatten!(1) #=> [1, 2, 3, [4, 5]]