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Mutable vs. Immutable

1:37 with andi mitre

In this video we’ll get a quick overview of the different data structures that Scala has to offer. We will take a look at the mutable and immutable collections and how to import each one.

New Terms:

Immutable collections -- A collection which cannot be updated or extended in place such as lists.
Mutable collections -- A collection which can be updated or extended in place instead of yielding a new collection such as arrays.

Further Reading:

Mutable and Immutable Collections

  • 0:00

    [MUSIC]

  • 0:04

    Hi, welcome to Scala Collections.

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    In the following videos we'll learn about collections in Scala.

  • 0:11

    Collections are a crucial part of any language and

  • 0:14

    they can range from immutable to mutable.

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    A mutable collection can be extended or it's contents can be updated in place.

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    Whereas immutable collection never changes.

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    Be aware that certain immutable collections may have methods to which can

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    update, add or remove elements but these operations will always yield

  • 0:35

    a new collection and leaves the existing collection intact.

  • 0:39

    Scala gives preference to immutable collections.

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    Scala collection classes can be found in scala.collection pagkage

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    which contains the sub packages scala.collection.immutable and

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    scala.collection.mutable.

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    The immutable package contains collections which guarantee that the elements

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    will not change.

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    Meanwhile scala.collection.mutable provides us with operations

  • 1:04

    to change the collections in place.

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    For instance a raise in scala are considered mutable

  • 1:10

    because we can update the values of the array.

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    While list are considered immutable because we're not able to update elements

  • 1:18

    within a list.

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    However you'll notice that we are able to append or prepend elements to our list.

  • 1:25

    Remember in that case a new collection will be created and

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    the original list will remain untouched.

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    In the following videos we'll dive deeper into scalar collections and

  • 1:35

    begin using them in our projects.

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