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instance method
Array#flatten!
array.flatten! → self or nil
array.flatten!(level) → self or nil
array.c
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static VALUE
rb_ary_flatten_bang(int argc, VALUE *argv, VALUE ary)
{
int mod = 0, level = -1;
VALUE result, lv;
lv = (rb_check_arity(argc, 0, 1) ? argv[0] : Qnil);
rb_ary_modify_check(ary);
if (!NIL_P(lv)) level = NUM2INT(lv);
if (level == 0) return Qnil;
result = flatten(ary, level);
if (result == ary) {
return Qnil;
}
if (!(mod = ARY_EMBED_P(result))) rb_obj_freeze(result);
rb_ary_replace(ary, result);
if (mod) ARY_SET_EMBED_LEN(result, 0);
return ary;
}
Replaces each nested Array in self with the elements from that Array; returns self if any changes, nil otherwise.
With non-negative Integer argument level, flattens recursively through level levels:
Example
a = [ 0, [ 1, [2, 3], 4 ], 5 ] a.flatten!(1) # => [0, 1, [2, 3], 4, 5] a = [ 0, [ 1, [2, 3], 4 ], 5 ] a.flatten!(2) # => [0, 1, 2, 3, 4, 5] a = [ 0, [ 1, [2, 3], 4 ], 5 ] a.flatten!(3) # => [0, 1, 2, 3, 4, 5] [0, 1, 2].flatten!(1) # => nil
With no argument, a nil argument, or with negative argument level, flattens all levels:
Example
a = [ 0, [ 1, [2, 3], 4 ], 5 ] a.flatten! # => [0, 1, 2, 3, 4, 5] [0, 1, 2].flatten! # => nil a = [ 0, [ 1, [2, 3], 4 ], 5 ] a.flatten!(-1) # => [0, 1, 2, 3, 4, 5] a = [ 0, [ 1, [2, 3], 4 ], 5 ] a.flatten!(-2) # => [0, 1, 2, 3, 4, 5] [0, 1, 2].flatten!(-1) # => nil