node/deps/npm/node_modules/extsprintf/README.md
Rebecca Turner 468ab4519e deps: upgrade npm to 6.1.0
PR-URL: https://github.com/nodejs/node/pull/20190
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Tiancheng "Timothy" Gu <timothygu99@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
2018-05-24 23:24:45 -07:00

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# 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.