47 lines
1.3 KiB
Markdown
47 lines
1.3 KiB
Markdown
# extsprintf: extended POSIX-style sprintf
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Stripped down version of s[n]printf(3c). We make a best effort to throw an
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exception when given a format string we don't understand, rather than ignoring
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it, so that we won't break existing programs if/when we go implement the rest
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of this.
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This implementation currently supports specifying
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* field alignment ('-' flag),
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* zero-pad ('0' flag)
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* always show numeric sign ('+' flag),
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* field width
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* conversions for strings, decimal integers, and floats (numbers).
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* argument size specifiers. These are all accepted but ignored, since
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Javascript has no notion of the physical size of an argument.
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Everything else is currently unsupported, most notably: precision, unsigned
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numbers, non-decimal numbers, and characters.
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Besides the usual POSIX conversions, this implementation supports:
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* `%j`: pretty-print a JSON object (using node's "inspect")
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* `%r`: pretty-print an Error object
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# Example
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First, install it:
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# npm install extsprintf
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Now, use it:
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var mod_extsprintf = require('extsprintf');
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console.log(mod_extsprintf.sprintf('hello %25s', 'world'));
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outputs:
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hello world
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# Also supported
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**printf**: same args as sprintf, but prints the result to stdout
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**fprintf**: same args as sprintf, preceded by a Node stream. Prints the result
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to the given stream.
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