wrapline

Add a prefix and/or suffix each line of a text stream.

This package used to be named indent-stream until 2.0.0 when the ability to add suffixes was added. Still proves good for indenting streams.

Examples

Indent each line of a stream

var WrapLine = require('wrapline')
var stream = WrapLine()
fs.createReadStream('before.txt')
.pipe(WrapLine('  ')) // indent entire stream with 2 spaces
.pipe(fs.createWriteStream('after.txt'))

Input:

Lorem ipsum dolor sit amet, quo ad quis latine.
Erant scribentur ne ius.
Nostrud vocibus luptatum eam ex, mel novum delenit scaevola no.
No iriure mentitum platonem usu, te nec ocurreret instructior.
Vim quem quis at.

Output:

  Lorem ipsum dolor sit amet, quo ad quis latine.
  Erant scribentur ne ius.
  Nostrud vocibus luptatum eam ex, mel novum delenit scaevola no.
  No iriure mentitum platonem usu, te nec ocurreret instructior.
  Vim quem quis at.

Add prefix/suffix to each line

var WrapLine = require('wrapline')
var stream = WrapLine()
fs.createReadStream('before.txt')
.pipe(WrapLine('<', '>')) // <surround line contents>
.pipe(fs.createWriteStream('after.txt'))

<Lorem ipsum dolor sit amet, quo ad quis latine.>
<Erant scribentur ne ius.>

Dynamically add prefix/suffix to each line

e.g. Adding line numbers

var WrapLine = require('wrapline')
var stream = WrapLine()
fs.createReadStream('before.txt')
.pipe(WrapLine(' ')) // add space
.pipe(WrapLine(function(pre, line) {
  // add 'line numbers' to each line
  pre = pre || 0
  return pre + 1
}))
.pipe(fs.createWriteStream('after.txt'))

1 Lorem ipsum dolor sit amet, quo ad quis latine.
2 Erant scribentur ne ius.
3 Nostrud vocibus luptatum eam ex, mel novum delenit scaevola no.
4 No iriure mentitum platonem usu, te nec ocurreret instructior.
5 Vim quem quis at.

See Also

• neoziro/stream-line-wrapper
• hughsk/wrapstream

License

MIT