@extra-array/has-prefix/README.md

Checks if array starts with a prefix.

Checks if array starts with a prefix.
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> Similar: [prefix], [prefixes], [hasPrefix].<br>
> Similar: [hasValue], [hasPrefix], [hasInfix], [hasSuffix], [hasSubsequence], [hasPermutation], [hasPath].

> This is part of package [extra-array].

[extra-array]: https://www.npmjs.com/package/extra-array

<br>

```javascript
array.hasPrefix(x, y, [fc], [fm]);
// x:  an array
// y:  prefix?
// fc: compare function (a, b)
// fm: map function (v, i, x)
```

```javascript
const array = require("extra-array");

var x = [1, 2, 3, 4];
array.hasPrefix(x, [1, 2]);
// true

array.hasPrefix(x, [-1, -2]);
// false

array.hasPrefix(x, [-1, -2], (a, b) => Math.abs(a) - Math.abs(b));
// true

array.hasPrefix(x, [-1, -2], null, v => Math.abs(v));
// true
```

<br>
<br>


## References

- [Data.List.isPrefixOf: Haskell](https://hackage.haskell.org/package/base-4.12.0.0/docs/Data-List.html#v:isPrefixOf)
- [List-Extra.isPrefixOf: elm](https://package.elm-lang.org/packages/elm-community/list-extra/7.1.0/List-Extra#isPrefixOf)
- [String.prototype.startsWith: MDN web docs](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/startsWith)
- [iterable-starts-with: @oprogramador](https://www.npmjs.com/package/iterable-starts-with)

[prefix]: https://github.com/nodef/extra-array/wiki/prefix
[prefixes]: https://github.com/nodef/extra-array/wiki/prefixes
[hasPrefix]: https://github.com/nodef/extra-array/wiki/hasPrefix
[hasValue]: https://github.com/nodef/extra-array/wiki/hasValue
[hasInfix]: https://github.com/nodef/extra-array/wiki/hasInfix
[hasSuffix]: https://github.com/nodef/extra-array/wiki/hasSuffix
[hasSubsequence]: https://github.com/nodef/extra-array/wiki/hasSubsequence
[hasPermutation]: https://github.com/nodef/extra-array/wiki/hasPermutation
[hasPath]: https://github.com/nodef/extra-array/wiki/hasPath