concat(*args) public

Appends the elements of other_arys to self.

[ "a", "b" ].concat( ["c", "d"])   #=> [ "a", "b", "c", "d" ]
[ "a" ].concat( ["b"], ["c", "d"]) #=> [ "a", "b", "c", "d" ]
[ "a" ].concat #=> [ "a" ]

a = [ 1, 2, 3 ]
a.concat( [ 4, 5 ])
a                                 #=> [ 1, 2, 3, 4, 5 ]

a = [ 1, 2 ]
a.concat(a, a)                    #=> [1, 2, 1, 2, 1, 2]

See also Array#+.

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May 3, 2010 - (<= v1_8_7_72)
2 thanks

Changes self

This method changes the object/array the method is called on. For example:

a = ["a", "b", "c"]
b = ["x", "y", "z"]

a.concat(b)  #=> [a", "b", "c", "z", "y", "z"]
a #=> [a", "b", "c", "z", "y", "z"]

In this example the object A is modified, the method modifies the object, then returns the new object.