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History of golang.

By David Li on Fri, 21 October 2024

Go’s design is influenced by C and its syntax is similar to C, making it easy for C programmers to learn Go. However, Go includes modern language features, such as garbage collection, concurrent programming, and memory safety. These features make Go a popular choice for building high-performance, scalable, and distributed systems.

Some of the basic concepts of Go programming include:

Packages

Go programs are organized into packages, which are collections of related Go source files. A package is a way to group related functions, types, and variables together into a single unit that can be easily imported and reused in other programs.

Functions

Functions are the building blocks of Go programs. A function is a block of code that performs a specific task. Functions can have input parameters and return values, or they can have no parameters and no return value.

Variables

Variables are used to store data in a Go program. A variable is a named storage location that has a specific type, such as int, float64, or string. Go is a statically typed language, which means that variables must be declared with a specific type before they can be used.

Control Structures

Control structures are used to control the flow of execution in a Go program. The most common control structures in Go are if/else statements, for loops, and switch statements.

Pointers

A pointer is a variable that holds the memory address of another variable. Pointers are used to pass large data structures efficiently between functions, and to modify data in place.

Structs

A struct is a composite data type that groups together zero or more values with different types under a single name. Structs are used to create complex data structures that can be passed between functions and used throughout a Go program.

In summary, Go is a modern programming language that is designed for simplicity, efficiency, and scalability. Its basic concepts include packages, functions, variables, control structures, pointers, and structs. These concepts form the foundation of Go programming, and are essential for building high-performance, scalable, and distributed systems.

Variables and constants are used to store and manipulate data in a Go program. In this section, we will discuss the differences between variables and constants, and how to declare and use them in a Go program.

Variables

A variable is a named storage location that holds a value of a specific type. In Go, variables must be declared before they can be used. To declare a variable, you use the var keyword followed by the variable name, the type of the variable, and an optional initial value. Here’s an example:

var message string = "Hello, World!"

In this example, we declare a variable named message of type string and assign it the value "Hello, World!". We can also declare multiple variables in a single statement, like this:

var x, y int = 10, 20

In this example, we declare two variables x and y of type int and assign them the values 10 and 20, respectively.

If you omit the initial value, Go will automatically set the variable to its “zero value”. The zero value depends on the type of the variable. For example, the zero value of an int variable is 0, and the zero value of a string variable is "" (an empty string). Here’s an example:

var count int // count is set to 0
var name string // name is set to ""

You can also use the := shorthand to declare and initialize a variable in a single statement, like this:

message := "Hello, World!"

In this example, Go automatically infers the type of the variable based on the initial value.

Constants

A constant is a named value that cannot be changed during the execution of a program. In Go, constants are declared using the const keyword followed by the constant name, the type of the constant (which can be omitted if the type can be inferred), and the value of the constant. Here’s an example:

const pi = 3.14159

In this example, we declare a constant named pi of type float64 and assign it the value 3.14159. Constants can also be declared in a group, like this:

const (
 monday = "Monday"
 tuesday = "Tuesday"
 wednesday = "Wednesday"
)

In this example, we declare three constants monday, tuesday, and wednesday of type string and assign them the corresponding values.

Constants are useful for values that are used throughout a program and should not be changed, such as mathematical constants like pi, or values that define program behavior, such as error codes.

Conclusion

In this section, we discussed the differences between variables and constants, and how to declare and use them in a Go program. Variables are named storage locations that hold a value of a specific type and can be changed during the execution of a program. Constants are named values that cannot be changed during the execution of a program. By using variables and constants effectively, you can store and manipulate data in a Go program with ease.

In Go, like any other programming language, data types define the kind of data that a variable can hold. In this section, we will discuss the basic data types that are available in Go.

Numeric Types

Go supports several numeric data types, including integers and floating-point numbers. Here are some of the most commonly used numeric data types:

  • int: a signed integer type that can hold a range of values depending on the size of the int (e.g., int32, int64, etc.).
  • uint: an unsigned integer type that can hold only positive values (e.g., uint8, uint16, etc.).
  • float32: a floating-point type that can hold single-precision floating-point values.
  • float64: a floating-point type that can hold double-precision floating-point values.

Here’s an example of declaring variables of these types:

var x int = 10
var y uint = 20
var z float32 = 3.14

Boolean Type

The bool data type represents a boolean value, which can be either true or false. Here’s an example:

var a bool = true
var b bool = false

String Type

The string data type represents a sequence of characters. Strings are immutable in Go, which means that once a string is created, its contents cannot be changed. Here’s an example:

var message string = "Hello, World!"

Other Types

Go also supports other data types such as arrays, slices, maps, and structs, which are used to store and manipulate more complex data structures. We will cover these data types in more detail in later sections.

Type Conversion

Sometimes, it may be necessary to convert a variable from one data type to another. In Go, you can convert a variable from one type to another by using a type conversion expression. Here’s an example:

var x int32 = 10
var y int64 = int64(x)

In this example, we declare a variable x of type int32 and assign it the value 10. We then declare a variable y of type int64 and assign it the value of x, which we convert to int64 using a type conversion expression.

Conclusion

In this section, we discussed the basic data types that are available in Go, including numeric types, boolean types, and string types. We also covered type conversion, which is used to convert a variable from one data type to another. By understanding the different data types in Go, you can choose the appropriate type for your variables and ensure that your program works correctly.

In Go, operators are used to perform various operations on variables and constants. In this section, we will discuss the different types of operators that are available in Go.

Arithmetic Operators

Arithmetic operators are used to perform arithmetic operations such as addition, subtraction, multiplication, and division. Here are some of the most commonly used arithmetic operators in Go:

  • +: addition
  • -: subtraction
  • *: multiplication
  • /: division
  • %: remainder

Here’s an example:

var x int = 10
var y int = 5
var z int = x + y // z will be 15

Comparison Operators

Comparison operators are used to compare two values and return a boolean value. Here are some of the most commonly used comparison operators in Go:

  • ==: equal to
  • !=: not equal to
  • <: less than
  • >: greater than
  • <=: less than or equal to
  • >=: greater than or equal to

Here’s an example:

var x int = 10
var y int = 5
var result bool = x > y // result will be true

Logical Operators

Logical operators are used to combine two or more boolean values and return a boolean value. Here are the three logical operators that are available in Go:

  • &&: logical AND
  • ||: logical OR
  • !: logical NOT

Here’s an example:

var x bool = true
var y bool = false
var result bool = x && y // result will be false

Assignment Operators

Assignment operators are used to assign a value to a variable. Here are some of the most commonly used assignment operators in Go:

  • =: simple assignment
  • +=: addition assignment
  • -=: subtraction assignment
  • *=: multiplication assignment
  • /=: division assignment
  • %=: remainder assignment

Here’s an example:

var x int = 10
x += 5 // x will be 15

Bitwise Operators

Bitwise operators are used to perform bitwise operations on integers. Here are some of the most commonly used bitwise operators in Go:

  • &: bitwise AND
  • |: bitwise OR
  • ^: bitwise XOR
  • <<: left shift
  • >>: right shift

Here’s an example:

var x uint8 = 0b00001010
var y uint8 = 0b00000101
var z uint8 = x & y // z will be 0b00000000

Conclusion

In this section, we discussed the different types of operators that are available in Go, including arithmetic operators, comparison operators, logical operators, assignment operators, and bitwise operators. By understanding these operators, you can perform various operations on your variables and constants and build more complex programs.

Control structures are used in programming languages to control the flow of execution of a program. In this section, we will discuss the control structures that are available in Go.

Conditional Statements

Conditional statements are used to execute different blocks of code based on the value of a condition. Here are the two conditional statements that are available in Go:

If Statement

The if statement is used to execute a block of code if a condition is true. Here’s an example:

var x int = 10
if x > 5 {
 fmt.Println("x is greater than 5")
}

If-else Statement

The if-else statement is used to execute a block of code if a condition is true, and another block of code if the condition is false. Here’s an example:

var x int = 10
if x > 5 {
 fmt.Println("x is greater than 5")
} else {
 fmt.Println("x is less than or equal to 5")
}

Looping Statements

Looping statements are used to execute a block of code repeatedly. Here are the three looping statements that are available in Go:

For Loop

The for loop is used to execute a block of code a fixed number of times. Here’s an example:

for i := 0; i < 5; i++ {
 fmt.Println(i)
}

While Loop

Go doesn’t have a dedicated while loop, but you can simulate one using the for loop. Here’s an example:

var i int = 0
for i < 5 {
 fmt.Println(i)
 i++
}

Infinite Loop

The infinite loop is used to execute a block of code indefinitely. Here’s an example:

for {
 fmt.Println("Hello, world!")
}

You can exit an infinite loop using the break statement.

Conclusion

In this section, we discussed the control structures that are available in Go, including conditional statements and looping statements. By using these control structures, you can control the flow of execution of your program and build more complex programs.

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