untabify

Convert all tabs in a string to multiple spaces & vice versa, preserving columns.

npm install untabify

Why?

Suppose you have a string

.»      ..»     ...»    »       ....»   .....»  ......» ............»   .

(» here represents a beginning of a tab char)

Its real length is 42. But if you print that string via console.log(), it consumes 73 columns in the xterm terminal.

There are several questios on SO like "How to determine the printed length of a string with tab characters expanded?" but no useful answers.

Well, the answer is obvious if we have untabify() function.

Examples

let untabify = require('untabify').untabify

let t1 = '.\t..\t...\t\t....\t.....\t......\t............\t.'
console.log(t1)
console.log(t1.length)
console.log(untabify(t1))
console.log(untabify(t1).length)
console.log(untabify(t1, 8, '»'))

which prints:

.       ..      ...             ....    .....   ......  ............    .
42
.       ..      ...             ....    .....   ......  ............    .
73
.»      ..»     ...»    »       ....»   .....»  ......» ............»   .

There is also tabify() as well. It works not like unexpand(1), but more like Emacs tabify function, i.e. it tries to preserve the visual formatting.

let assert = require('assert')
let tabify = require('untabify').tabify

assert.equal('      1\t1\t2', tabify('      1 1       2'))

Where are the tests?

In the end of index.js file.

License

MIT.