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printf, sprintf, and vsprintf for JavaScript

version 0.2.2 on npm node version 0.4 and up MIT License


npm install format

The code works in browsers as well, you can copy these functions into your project or otherwise include them with your other JavaScript.


var format = require('format')
  , printf = format.printf
  , vsprintf = format.vsprintf
  // or if you want to keep it old school
  , sprintf = format

// Print 'hello world'
printf('%s world', 'hello')

var what = 'life, the universe, and everything'
format('%d is the answer to %s', 42, what)
// => '42 is the answer to life, the universe, and everything'

vsprintf('%d is the answer to %s', [42, what])
// => '42 is the answer to life, the universe, and everything'

// you can format values as JSON with %j
var value = {answer: 42}
format('%j', value)
// => '{"answer":42}'

Supported format specifiers: b, c, d, f, j, o, s, x, and X.

See man 3 printf or man 1 printf for details. j is an extension that formats values as JSON.

Precision is supported for floating point numbers.


Copyright 2010 - 2016 Sami Samhuri

MIT license