https://github.com/lamansky/sbo
Support the Bind Operator. Converts value::yourFunction(arg) to yourFunction(value, arg)—but lets your function support either.
https://github.com/lamansky/sbo
Last synced: 2 months ago
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Support the Bind Operator. Converts value::yourFunction(arg) to yourFunction(value, arg)—but lets your function support either.
- Host: GitHub
- URL: https://github.com/lamansky/sbo
- Owner: lamansky
- License: mit
- Created: 2018-02-03T16:09:43.000Z (over 8 years ago)
- Default Branch: master
- Last Pushed: 2021-11-03T04:27:28.000Z (over 4 years ago)
- Last Synced: 2025-11-05T19:35:34.593Z (8 months ago)
- Language: JavaScript
- Homepage:
- Size: 8.79 KB
- Stars: 0
- Watchers: 1
- Forks: 1
- Open Issues: 0
-
Metadata Files:
- Readme: readme.md
- License: license.txt
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README
# sbo
SBO stands for Support the [Bind Operator](https://github.com/tc39/proposal-bind-operator).
Converts `value::yourFunction(arg)` to `yourFunction(value, arg)`—but lets your function support either.
## Installation
Requires [Node.js](https://nodejs.org/) 6.0.0 or above.
```bash
npm i sbo
```
## API
The module exports a single function.
### Parameters
1. Optional: Object argument:
* Optional: `arg` (integer): The argument index at which `this` should be inserted. Defaults to `0`.
* Optional: `path` (string): The dot-separated key path of an options object argument located at index `arg` into which `this` should be inserted.
* Optional: `ignoreThis` (object, array, or function): `this` is ignored if `ignoreThis` strictly equals `this`, or if `ignoreThis` is an array containing `this`, or if `ignoreThis` is a function which returns `true` when given `this`.
2. `fn` (Function): The function which should receive bind operator support.
### Return Value
A wrapper function with bind operator support that calls `fn`.
## Tutorial
Let’s say, for the sake of example, that you have a function called `addSuffix`:
```javascript
const addSuffix = (str, suffix) => str + suffix
```
You use the `sbo` module to add support for the bind operator:
```javascript
const supportBindOperator = require('sbo')
const addSuffix = supportBindOperator((str, suffix) => str + suffix)
```
Now your function can be called either the normal way or with the bind operator:
```javascript
addSuffix('Hello, world', '!') // 'Hello, world!'
'Hello, world'::addSuffix('!') // 'Hello, world!'
```
### Specifying a Parameter Index
Now let’s swap the order of the parameters:
```javascript
const addSuffix = (suffix, str) => str + suffix
```
A bound `this` would now need to become the argument with an index of 1. To do this, pass an extra argument to `sbo`:
```javascript
const supportBindOperator = require('sbo')
const addSuffix = supportBindOperator({arg: 1}, (suffix, str) => str + suffix)
addSuffix('!', 'Hello, world') // 'Hello, world!'
'Hello, world'::addSuffix('!') // 'Hello, world!'
```
### Specifying an Object Argument Key
Let’s try using a deconstructed object parameter:
```javascript
const addSuffix = ({str, suffix}) => str + suffix
```
Do the following to direct a bound `this` to the `str` key of the object argument at index zero (i.e. the first, and in this case the only, argument):
```javascript
const supportBindOperator = require('sbo')
const addSuffix = supportBindOperator({path: 'str'}, ({str, suffix}) => str + suffix)
addSuffix({str: 'Hello, world', suffix: '!'}) // 'Hello, world!'
'Hello, world'::addSuffix({suffix: '!'}) // 'Hello, world!'
```
If you have a nested object parameter, you can use a dot-separated key path.
## Related
Check out these other function utility packages.
* [efn](https://github.com/lamansky/efn): Extracted Function
* [ffn](https://github.com/lamansky/ffn): Filtering Function
* [jfn](https://github.com/lamansky/jfn): Joined Function
* [mfn](https://github.com/lamansky/mfn): Memoized Function
* [ofn](https://github.com/lamansky/ofn): Overloaded Function
* [pfn](https://github.com/lamansky/pfn): Possible Function
* [qfn](https://github.com/lamansky/qfn): Qualified Function
* [vfn](https://github.com/lamansky/vfn): Variadic Function
* [wfn](https://github.com/lamansky/wfn): Wrapper Function
* [xfn](https://github.com/lamansky/xfn): Extended Function
* [3fn](https://github.com/lamansky/3fn): Three-Way Comparison Function