github.com/ylin610/units

Description

This package provides type Bytes, which implements fmt.Formatter and can be easily formatted to various human-readable string using std fmt package.

It also has some mathematics methods to modify the value. See example_test.go.

Formatting

The formatting result typically consists of a number and a unit.

There are binary units (kiB, MiB, GiB and TiB), decimal units (kB, MB, GB and TB) and base unit B. Further reading here.

When calculating the output number, binary units are used by default. You can switch to decimal units by adding the # flag.

Why is there no PiB/PB? TiB/TB is sufficient for most cases, and many non-technical people are not familiar with PiB/PB.

Verbs

• s: format to an integer number and a proper unit.

  fmt.Sprintf("%s", units.Bytes(1023)) // 1023B
  fmt.Sprintf("%s", units.Bytes(1024)) // 1kiB
  fmt.Sprintf("%s", units.Bytes(1025)) // 1kiB
  

• f: format to a float number and a proper unit, default precision is 1.

  fmt.Sprintf("%f", units.Bytes(1023)) // 1023.0B
  fmt.Sprintf("%f", units.Bytes(1024)) // 1.0kiB
  fmt.Sprintf("%f", units.Bytes(1150)) // 1.1kiB
  

• v: equal to s.

• k: format to an integer number with the unit kiB.

  fmt.Sprintf("%k", units.Bytes(1<<9)) // 0B
  fmt.Sprintf("%k", units.Bytes(1<<10)) // 1kiB
  fmt.Sprintf("%k", units.Bytes(1<<20)) // 1024kiB
  

• m: format to an integer number with the unit MiB.

• g: format to an integer number with the unit GiB.

• t: format to an integer number with the unit TiB.

Flags

• #: use decimal units.

  fmt.Sprintf("%f", 10*units.KiB) // 10.0kiB
  fmt.Sprintf("%#f", 10*units.KiB) // 10.2kB
  

• : (space) do not output the unit.

  fmt.Sprintf("%s", units.KiB) // 1kiB
  fmt.Sprintf("% s", units.KiB) // 1
  

Sign for numbers (+), left-justify (-) and zero padding (0) are not supported.

Width and precision

The width includes the unit.

fmt.Sprintf("%4s", units.KiB)    //    " 1kiB"
fmt.Sprintf("%8.2f", units.KiB)  // " 1.00kiB"
fmt.Sprintf("% 8.2f", units.KiB) // "    1.00"