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# locate-character
Get the line and column number of a particular character in a string.
## Installation
`npm install locate-character`, or get it from [unpkg.com/locate-character](https://unpkg.com/locate-character).
## Usage
To search for a particular character, using the index or a search string, use `locate`:
```js
import { locate } from 'locate-character';
const sample = `
A flea and a fly in a flue
Were imprisoned, so what could they do?
Said the fly, "let us flee!"
"Let us fly!" said the flea.
So they flew through a flaw in the flue.
`.trim();
// Using a character index
const index = sample.indexOf('fly');
locate(sample, index);
// -> { line: 0, column: 13, character: 13 }
// Using the string itself
locate(sample, 'fly');
// -> { line: 0, column: 13, character: 13 }
// Using the string with a start index
locate(sample, 'fly', { startIndex: 14 });
// -> { line: 2, column: 9, character: 76 }
```
If you will be searching the same string repeatedly, it's much faster if you use `getLocator`:
```js
import { getLocator } from 'locate-character';
const locate = getLocator(sample);
let location = locate(13);
// -> { line: 0, column: 13, character: 13 }
location = locate('fly', { startIndex: location.character + 1 });
// -> { line: 2, column: 9, character: 76 }
location = locate('fly', { startIndex: location.character + 1 });
// -> { line: 3, column: 8, character: 104 }
```
In some situations (for example, dealing with sourcemaps), you need one-based line numbers:
```js
getLocator(sample, { offsetLine: 1 });
locate(sample, { offsetLine: 1 });
```
There's also an `offsetColumn` option which is less useful in real-world situations.
## License
MIT