Skip to content

feat: add string/base/for-each-code-point-right #2163

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
Show file tree
Hide file tree
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
Original file line number Diff line number Diff line change
@@ -0,0 +1,146 @@
<!--

@license Apache-2.0

Copyright (c) 2024 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.

-->

# forEachCodePointRight

> Invokes a function for each Unicode code point in a string, 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 forEachCodePointRight = require( '@stdlib/string/base/for-each-code-point-right' );
```

#### forEachCodePointRight( str, clbk\[, thisArg ] )

Invokes a function for each Unicode code point in a string, iterating from right to left.

```javascript
function log( value, index ) {
console.log( '%d: %s', index, value );
}

forEachCodePointRight( 'Beep!', log );
/* =>
4: !
3: p
2: e
1: e
0: B
*/
```

The invoked function is provided three arguments:

- **value**: Unicode code point.
- **index**: starting Unicode code point index.
- **str**: input string.

To set the function execution context, provide a `thisArg`.

```javascript
function clbk() {
this.count += 1;
}

var str = '👉🏿';

var ctx = {
'count': 0
};

forEachCodePointRight( str, clbk, ctx );

var cnt = ctx.count;
// returns 2
```

</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">

</section>

<!-- /.notes -->

<!-- Package usage examples. -->

<section class="examples">

## Examples

<!-- eslint no-undef: "error" -->

```javascript
var forEachCodePointRight = require( '@stdlib/string/base/for-each-code-point-right' );

function log( value, index ) {
console.log( '%d: %s', index, value );
}

forEachCodePointRight( 'presidential election', log );
forEachCodePointRight( 'Iñtërnâtiônàlizætiøn', log );
forEachCodePointRight( '🌷🍕', log );
forEachCodePointRight( '\uD834\uDD1E', log );
```

</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 related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->

<section class="related">

</section>

<!-- /.related -->

<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="links">

</section>

<!-- /.links -->
Original file line number Diff line number Diff line change
@@ -0,0 +1,61 @@
/**
* @license Apache-2.0
*
* Copyright (c) 2024 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.
*/

'use strict';

// MODULES //

var bench = require( '@stdlib/bench' );
var isString = require( '@stdlib/assert/is-string' ).isPrimitive;
var pkg = require( './../package.json' ).name;
var forEachRight = require( './../lib' );


// MAIN //

bench( pkg, function benchmark( b ) {
var values;
var out;
var i;

values = [
'Iñtërnâtiônàlizætiøn',
'presidential election',
'🐶🐮🐷🐰🐸'
];

b.tic();
for ( i = 0; i < b.iterations; i++ ) {
out = forEachRight( values[ i%values.length ], clbk );
if ( typeof out !== 'string' ) {
b.fail( 'should return a string' );
}
}
b.toc();
if ( !isString( out ) ) {
b.fail( 'should return a string' );
}
b.pass( 'benchmark finished' );
b.end();

function clbk( v ) {
if ( typeof v !== 'string' ) {
b.fail( 'unexpected value' );
}
}
});
Original file line number Diff line number Diff line change
@@ -0,0 +1,38 @@

{{alias}}( str, clbk[, thisArg] )
Invokes a function for each Unicode code point in a string, iterating from
right to left.

When invoked, the provided function is provided three arguments:

- value: code point
- index: starting code point index
- str: input string

Parameters
----------
str: string
Input string over which to iterate.

clbk: Function
The function to invoke for each Unicode code point in the input string.

thisArg: any (optional)
Execution context.

Returns
-------
out: string
Input string.

Examples
--------
> var n = 0;
> function fcn() { n += 1; };
> {{alias}}( 'hello world!', fcn );
> n
12

See Also
--------

Original file line number Diff line number Diff line change
@@ -0,0 +1,93 @@
/**
* @license Apache-2.0
*
* Copyright (c) 2024 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.
*/

// TypeScript Version: 4.1

/**
* Callback invoked for each Unicode code point in a string.
*
* @returns result
*/
type Nullary<T> = ( this: T ) => any;

/**
* Callback invoked for each Unicode code point in a string.
*
* @param value - code point
* @returns result
*/
type Unary<T> = ( this: T, value: string ) => any;

/**
* Callback invoked for each Unicode code point in a string.
*
* @param value - code point
* @param index - starting code point index
* @returns result
*/
type Binary<T> = ( this: T, value: string, index: number ) => any;

/**
* Callback invoked for each Unicode code point in a string.
*
* @param value - code point
* @param index - starting code point index
* @param str - input string
* @returns result
*/
type Ternary<T> = ( this: T, value: string, index: number, str: string ) => any;

/**
* Callback invoked for each Unicode code point in a string.
*
* @param value - code point
* @param index - starting code point index
* @param str - input string
* @returns result
*/
type Callback<T> = Nullary<T> | Unary<T> | Binary<T> | Ternary<T>;

/**
* Invokes a function for each Unicode code point in a string, iterating from right to left.
*
* ## Notes
*
* - When invoked, the provided function is provided three arguments:
*
* - **value**: code point.
* - **index**: starting code point index.
* - **str**: input string.
*
* @param str - input string
* @param clbk - function to invoke
* @param thisArg - execution context
* @returns input string
*
* @example
* function log( value, index ) {
* console.log( '%d: %s', index, value );
* }
*
* forEachRight( 'Hello, World!', log );
*/
declare function forEachRight<T = unknown>( str: string, clbk: Callback<T>, thisArg?: ThisParameterType<Callback<T>> ): string;


// EXPORTS //

export = forEachRight;
Loading