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Introduction to Scala

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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

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    [MUSIC] 0:00
    Hi, welcome to Scala Collections. 0:04
    In the following videos we'll learn about collections in Scala. 0:07
    Collections are a crucial part of any language and 0:11
    they can range from immutable to mutable. 0:14
    A mutable collection can be extended or it's contents can be updated in place. 0:17
    Whereas immutable collection never changes. 0:22
    Be aware that certain immutable collections may have methods to which can 0:26
    update, add or remove elements but these operations will always yield 0:30
    a new collection and leaves the existing collection intact. 0:35
    Scala gives preference to immutable collections. 0:39
    Scala collection classes can be found in scala.collection pagkage 0:42
    which contains the sub packages scala.collection.immutable and 0:47
    scala.collection.mutable. 0:51
    The immutable package contains collections which guarantee that the elements 0:54
    will not change. 0:58
    Meanwhile scala.collection.mutable provides us with operations 0:59
    to change the collections in place. 1:04
    For instance a raise in scala are considered mutable 1:07
    because we can update the values of the array. 1:10
    While list are considered immutable because we're not able to update elements 1:13
    within a list. 1:18
    However you'll notice that we are able to append or prepend elements to our list. 1:19
    Remember in that case a new collection will be created and 1:25
    the original list will remain untouched. 1:28
    In the following videos we'll dive deeper into scalar collections and 1:31
    begin using them in our projects. 1:35

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