thedesk/app/node_modules/extsprintf/README.md
2018-02-19 02:41:25 +09:00

1.3 KiB

extsprintf: extended POSIX-style sprintf

Stripped down version of s[n]printf(3c). We make a best effort to throw an
exception when given a format string we don't understand, rather than ignoring
it, so that we won't break existing programs if/when we go implement the rest
of this.

This implementation currently supports specifying

  • field alignment ('-' flag),
  • zero-pad ('0' flag)
  • always show numeric sign ('+' flag),
  • field width
  • conversions for strings, decimal integers, and floats (numbers).
  • argument size specifiers. These are all accepted but ignored, since
    Javascript has no notion of the physical size of an argument.

Everything else is currently unsupported, most notably: precision, unsigned
numbers, non-decimal numbers, and characters.

Besides the usual POSIX conversions, this implementation supports:

  • %j: pretty-print a JSON object (using node's "inspect")
  • %r: pretty-print an Error object

Example

First, install it:

# npm install extsprintf

Now, use it:

var mod_extsprintf = require('extsprintf');
console.log(mod_extsprintf.sprintf('hello %25s', 'world'));

outputs:

hello                     world

Also supported

printf: same args as sprintf, but prints the result to stdout

fprintf: same args as sprintf, preceded by a Node stream. Prints the result
to the given stream.