206 lines
4.7 KiB
Markdown
206 lines
4.7 KiB
Markdown
<!--
|
|
|
|
@license Apache-2.0
|
|
|
|
Copyright (c) 2018 The Stdlib Authors.
|
|
|
|
Licensed under the Apache License, Version 2.0 (the "License");
|
|
you may not use this file except in compliance with the License.
|
|
You may obtain a copy of the License at
|
|
|
|
http://www.apache.org/licenses/LICENSE-2.0
|
|
|
|
Unless required by applicable law or agreed to in writing, software
|
|
distributed under the License is distributed on an "AS IS" BASIS,
|
|
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
See the License for the specific language governing permissions and
|
|
limitations under the License.
|
|
|
|
-->
|
|
|
|
# noneByRight
|
|
|
|
> Test whether all elements in a collection fail a test implemented by a predicate function, iterating from right to left.
|
|
|
|
<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->
|
|
|
|
<section class="intro">
|
|
|
|
</section>
|
|
|
|
<!-- /.intro -->
|
|
|
|
<!-- Package usage documentation. -->
|
|
|
|
<section class="usage">
|
|
|
|
## Usage
|
|
|
|
```javascript
|
|
var noneByRight = require( '@stdlib/utils/none-by-right' );
|
|
```
|
|
|
|
#### noneByRight( collection, predicate\[, thisArg ] )
|
|
|
|
Tests whether all elements in a `collection` fail a test implemented by a `predicate` function, iterating from right to left.
|
|
|
|
```javascript
|
|
function isPositive( value ) {
|
|
return ( value > 0 );
|
|
}
|
|
|
|
var arr = [ -1, -2, -3, -4 ];
|
|
|
|
var bool = noneByRight( arr, isPositive );
|
|
// returns true
|
|
```
|
|
|
|
If a `predicate` function returns a truthy value, the function **immediately** returns `false`.
|
|
|
|
```javascript
|
|
function isPositive( value ) {
|
|
return ( value > 0 );
|
|
}
|
|
|
|
var arr = [ -1, 2, -3, -4 ];
|
|
|
|
var bool = noneByRight( arr, isPositive );
|
|
// returns false
|
|
```
|
|
|
|
The invoked `function` is provided three arguments:
|
|
|
|
- `value`: collection element
|
|
- `index`: collection index
|
|
- `collection`: input collection
|
|
|
|
To set the function execution context, provide a `thisArg`.
|
|
|
|
```javascript
|
|
function sum( value ) {
|
|
if ( value < 0 ) {
|
|
return true;
|
|
}
|
|
this.sum += value;
|
|
this.count += 1;
|
|
return false;
|
|
}
|
|
|
|
var arr = [ 1, 2, 3, 4 ];
|
|
|
|
var context = {
|
|
'sum': 0,
|
|
'count': 0
|
|
};
|
|
|
|
var bool = noneByRight( arr, sum, context );
|
|
// returns true
|
|
|
|
var mean = context.sum / context.count;
|
|
// returns 2.5
|
|
```
|
|
|
|
</section>
|
|
|
|
<!-- /.usage -->
|
|
|
|
<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
|
|
|
|
<section class="notes">
|
|
|
|
## Notes
|
|
|
|
- A `collection` may be either an [`Array`][mdn-array], [`Typed Array`][mdn-typed-array], or an array-like [`Object`][mdn-object] (excluding `strings` and `functions`).
|
|
|
|
- If provided an empty collection, the function returns `true`.
|
|
|
|
```javascript
|
|
function truthy() {
|
|
return true;
|
|
}
|
|
var bool = noneByRight( [], truthy );
|
|
// returns true
|
|
```
|
|
|
|
- The function does **not** skip `undefined` elements.
|
|
|
|
<!-- eslint-disable no-sparse-arrays, stdlib/doctest-marker -->
|
|
|
|
```javascript
|
|
function log( value, index ) {
|
|
console.log( '%s: %s', index, value );
|
|
return false;
|
|
}
|
|
|
|
var arr = [ 1, , , 4 ];
|
|
|
|
var bool = noneByRight( arr, log );
|
|
/* =>
|
|
3: 4
|
|
2: undefined
|
|
1: undefined
|
|
0: 1
|
|
*/
|
|
```
|
|
|
|
- The function provides limited support for dynamic collections (i.e., collections whose `length` changes during execution). Note, however, that index incrementation is **not** guaranteed to be monotonically **decreasing**.
|
|
|
|
</section>
|
|
|
|
<!-- /.notes -->
|
|
|
|
<!-- Package usage examples. -->
|
|
|
|
<section class="examples">
|
|
|
|
## Examples
|
|
|
|
<!-- eslint no-undef: "error" -->
|
|
|
|
```javascript
|
|
var randu = require( '@stdlib/random/base/randu' );
|
|
var noneByRight = require( '@stdlib/utils/none-by-right' );
|
|
|
|
function isPositive( value ) {
|
|
return ( value > 0 );
|
|
}
|
|
|
|
var bool;
|
|
var arr;
|
|
var i;
|
|
|
|
arr = new Array( 100 );
|
|
for ( i = 0; i < arr.length; i++ ) {
|
|
arr[ i ] = -randu();
|
|
}
|
|
|
|
bool = noneByRight( arr, isPositive );
|
|
// returns true
|
|
```
|
|
|
|
</section>
|
|
|
|
<!-- /.examples -->
|
|
|
|
<!-- Section to include cited references. If references are included, add a horizontal rule *before* the section. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
|
|
|
|
<section class="references">
|
|
|
|
</section>
|
|
|
|
<!-- /.references -->
|
|
|
|
<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
|
|
|
|
<section class="links">
|
|
|
|
[mdn-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array
|
|
|
|
[mdn-typed-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray
|
|
|
|
[mdn-object]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object
|
|
|
|
</section>
|
|
|
|
<!-- /.links -->
|