Zero Value

By Xah Lee. Date: . Last updated: .

Variables declared without an explicit initial value are given their default value.

Default value are different for different types of variables.

The default value for a type is called its “zero value”.

The zero values are:

package main

import "fmt"

func main() {

	var i int
	var f float64
	var b bool
	var str string
	var sl []int

	fmt.Printf("%#v\n", i)   // 0
	fmt.Printf("%#v\n", f)   // 0
	fmt.Printf("%#v\n", b)   // false
	fmt.Printf("%#v\n", str) // ""
	fmt.Printf("%#v\n", sl)  // []int(nil)

	// %#v means print in golang syntax
}

Reference

The Go Programming Language Specification - The Go Programming Language#The_zero_value

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Golang

  1. Compile, Run
  2. Source Encoding
  3. Package, Import
  4. Comment
  5. Print
  6. String
  7. String Functions
  8. Print String
  9. String Backslash Escape
  10. Rune
  11. Variable
  12. Zero Value
  13. Constant
  14. If Then Else
  15. Switch/Case
  16. Loop
  17. Basic Types
  18. Array
  19. Slice
  20. Map
  21. Struct
  22. Function
  23. Closure
  24. Pointer
  25. String, Byte Slice, Rune Slice
  26. regexp
  27. Read File
  28. Write to File
  29. Walk Dir
  30. Check File Exist
  31. System Call
  32. Get Script Path
  33. Defer
  34. Random Number

Examples

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  2. Find Replace
  3. Validate Links
  4. Generate Sitemap

Reference

  1. Go Spec