teddit/node_modules/extsprintf/README.md
2020-11-17 21:44:32 +01:00

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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.