Post2: Golang Print Functions

series: Golang

Printing Functions in Golang

In Golang, several functions are available for printing text, and each serves specific use cases. Here's an explanation of the most commonly used printing functions:

1. fmt.Print

Description:
Prints the provided arguments as plain text without adding a newline. It does not format the output.

Use Case:
For simple concatenated text or values where no specific formatting is required.

fmt.Print("Hello")          // Output: Hello
fmt.Print("World")          // Output: HelloWorld
fmt.Print(123, " GoLang")   // Output: HelloWorld123 GoLang

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2. fmt.Println

Description:
Prints the provided arguments as plain text and appends a newline at the end.

Use Case:
For simple outputs where you want automatic line breaks after printing.

fmt.Println("Hello")         // Output: Hello (with newline)
fmt.Println("World")         // Output: World (on a new line)
fmt.Println(123, "GoLang")   // Output: 123 GoLang (on a new line)

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3. fmt.Printf

Description:
Formats and prints text according to a specified format string. Does not add a newline unless explicitly included in the format string.

Use Case:
For dynamic or formatted outputs (e.g., integers, floats, strings, etc.).

name := "Alice"
age := 25
fmt.Printf("My name is %s and I am %d years old.", name, age)
// Output: My name is Alice and I am 25 years old.

Common Formatting Verbs:

Verb	Description	Example
%s	String	fmt.Printf("%s", "Go")
%d	Integer (base 10)	fmt.Printf("%d", 123)
%f	Floating-point	fmt.Printf("%.2f", 3.14)
%v	Default format for any value	fmt.Printf("%v", true)
%T	Type of the variable	fmt.Printf("%T", name)
%+v	Struct with field names	fmt.Printf("%+v", obj)

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4. fmt.Sprintf

Description:
Formats text like fmt.Printf, but instead of printing to the console, it returns the formatted string.

Use Case:
For preparing strings for later use (e.g., logging, building responses).

formatted := fmt.Sprintf("Hello, %s!", "Alice")
fmt.Println(formatted)
// Output: Hello, Alice!