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Introduction to GoLang
course content

Course Content

Introduction to GoLang

Introduction to GoLang

1. Getting Started
What is Go Programming Language?Hello WorldComments in GoBasics of VariablesModifying Variable ValuesConstantsBasics of Operators & ExpressionsChallenge: Hello WorldChallenge: Comments in GoChallenge: Basics of VariablesChallenge: Constants
2. Data Types
IntegersFloating-Point NumbersBooleansRunesStringsBasic Type CastingString FormattingChallenge: String Formatting Practice
3. Control Structures
Comparison OperatorsConditional StatementsConditional ChainingLogical OperatorsSwitch StatementFor LoopBreak StatementChallenge: Practicing For Loop
4. Functions
Declaring and Defining FunctionsLocal and Global ScopesPassing Data into the FunctionsReturn Values from FunctionsMultiple Return ValuesPassing Functions as ArgumentsChallenge: Reviewing Concepts of Functions
5. Arrays and Slices
Declaring ArraysAccessing and Modifying Array ElementsSlicesLength vs CapacityMulti-Dimensional ArraysIterating Over ArraysPassing Variable Number of Arguments into FunctionsPassing Arrays into FunctionsChallenge: Finding the Largest Element in a Grid
6. Intro to Structs & Maps
Creating StructsCreating Instances of StructsData in StructsWhat are Maps?Map Declaration and InitializationAccessing Map ValuesDeleting Keys From MapsChallenge: Creating a Structure

book
Map Declaration and Initialization

We can declare an empty map using the make() function. Below is the syntax we need to follow:

python

Here, mapName is the name of the map, keyType is the expected type of the keys, and valueType is the expected type of the values. The term map is a keyword.

We can declare a map called courseData with keys of type string and values of type int.

go

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1

            
var courseData = make(map[string]int)

If we attempt to output this map, we will receive an output indicating an empty map:

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1

            
fmt.Println(courseData) // Output: map[]

We can initialize a map with some data using the following syntax:

python

Note

You can place or omit spaces in the map declaration syntax; therefore, both map[keyType]valueType and map [keyType] valueType are valid.

Using the above syntax, we can create a map that has some initial data in it:

go

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1234567

            
myMap := map[string]int {
	"a": 10,
	"b": 11,
	"c": 12,
}

fmt.Println(myMap) // Output: map[a:10 b:11 c:12]
question mark

Which syntax is correct for creating a new empty map?

Select the correct answer

Everything was clear?

How can we improve it?

Thanks for your feedback!

SectionΒ 6. ChapterΒ 5
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