feat: add iter/cusome

lib/node_modules/@stdlib/iter/cusome/README.md

@@ -0,0 +1,158 @@
+<!--
+
+@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.
+
+-->
+
+# iterCuSome
+
+> Create an iterator which cumulatively tests whether at least `n` iterated values are truthy.
+
+<!-- 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 iterCuSome = require( '@stdlib/iter/cusome' );
+```
+
+#### iterCuSome( iterator, n )
+
+Returns an [iterator][mdn-iterator-protocol] which cumulatively tests whether at least `n` iterated values are truthy.
+
+```javascript
+var array2iterator = require( '@stdlib/array/to-iterator' );
+
+var arr = array2iterator( [ 0, 0, 1, 1, 0 ] );
+
+var it = iterCuSome( arr, 2 );
+
+var v = it.next().value;
+// returns false
+
+v = it.next().value;
+// returns false
+
+v = it.next().value;
+// returns false
+
+v = it.next().value;
+// returns true
+
+v = it.next().value;
+// returns true
+
+var bool = it.next().done;
+// returns true
+```
+
+The returned [iterator][mdn-iterator-protocol] protocol-compliant object has the following properties:
+
+-   **next**: function which returns an [iterator][mdn-iterator-protocol] protocol-compliant object containing the next iterated value (if one exists) assigned to a `value` property and a `done` property having a `boolean` value indicating whether the [iterator][mdn-iterator-protocol] is finished.
+-   **return**: function which closes an [iterator][mdn-iterator-protocol] and returns a single (optional) argument in an [iterator][mdn-iterator-protocol] protocol-compliant object.
+
+</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 randu = require( '@stdlib/random/iter/randu' );
+var iterMap = require( '@stdlib/iter/map' );
+var iterCuSome = require( '@stdlib/iter/cusome' );
+
+function threshold( r ) {
+    return ( r > 0.95 );
+}
+
+// Create an iterator which generates uniformly distributed pseudorandom numbers:
+var opts = {
+    'iter': 100
+};
+var riter = randu( opts );
+
+// Create an iterator which applies a threshold to generated numbers:
+var miter = iterMap( riter, threshold );
+
+// Create an iterator which cumulatively tests whether at least 5 iterated values are truthy:
+var it = iterCuSome( miter, 5 );
+
+// Perform manual iteration...
+var r;
+while ( true ) {
+    r = it.next();
+    if ( r.done ) {
+        break;
+    }
+    console.log( r.value );
+}
+```
+
+</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">
+
+[mdn-iterator-protocol]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Iteration_protocols#The_iterator_protocol
+
+</section>
+
+<!-- /.links -->

lib/node_modules/@stdlib/iter/cusome/benchmark/benchmark.js

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+/**
+* @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 isBoolean = require( '@stdlib/assert/is-boolean' ).isPrimitive;
+var isIteratorLike = require( '@stdlib/assert/is-iterator-like' );
+var iterConstant = require( '@stdlib/iter/constant' );
+var pkg = require( './../package.json' ).name;
+var iterCuSome = require( './../lib' );
+
+
+// MAIN //
+
+bench( pkg, function benchmark( b ) {
+	var iter;
+	var it;
+	var i;
+
+	it = iterConstant( 3.14 );
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		iter = iterCuSome( it, 2 );
+		if ( typeof iter !== 'object' ) {
+			b.fail( 'should return an object' );
+		}
+	}
+	b.toc();
+	if ( !isIteratorLike( iter ) ) {
+		b.fail( 'should return an iterator protocol-compliant object' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});
+
+bench( pkg+'::iteration', function benchmark( b ) {
+	var iter;
+	var v;
+	var i;
+
+	iter = iterCuSome( iterConstant( 3.14 ), b.iterations-1 );
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		v = iter.next().value;
+		if ( !isBoolean( v ) ) {
+			b.fail( 'should return a boolean' );
+		}
+	}
+	b.toc();
+	if ( !isBoolean( v ) ) {
+		b.fail( 'should return a boolean' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});

lib/node_modules/@stdlib/iter/cusome/docs/repl.txt

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+
+{{alias}}( iterator, n )
+    Returns an iterator which cumulatively tests whether at least `n` iterated
+    values are truthy.
+
+    If an environment supports Symbol.iterator and a provided iterator is
+    iterable, the returned iterator is iterable.
+
+    Parameters
+    ----------
+    iterator: Object
+        Input iterator.
+
+    n: integer
+        Minimum number of truthy values.
+
+    Returns
+    -------
+    iterator: Object
+        Iterator.
+
+    iterator.next(): Function
+        Returns an iterator protocol-compliant object containing the next
+        iterated value (if one exists) and a boolean flag indicating whether the
+        iterator is finished.
+
+    iterator.return( [value] ): Function
+        Finishes an iterator and returns a provided value.
+
+    Examples
+    --------
+    > var arr = {{alias:@stdlib/array/to-iterator}}( [ 0, 0, 1, 1, 0 ] );
+    > var it = {{alias}}( arr, 2 );
+    > var v = it.next().value
+    false
+    > v = it.next().value
+    false
+    > v = it.next().value
+    false
+    > v = it.next().value
+    true
+    > v = it.next().value
+    true
+
+    See Also
+    --------
+

lib/node_modules/@stdlib/iter/cusome/docs/types/index.d.ts

@@ -0,0 +1,65 @@
+/*
+* @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
+
+/// <reference types="@stdlib/types"/>
+
+import { Iterator as Iter, IterableIterator } from '@stdlib/types/iter';
+
+// Define a union type representing both iterable and non-iterable iterators:
+type Iterator = Iter | IterableIterator;
+
+/**
+* Returns an iterator which cumulatively tests whether at least `n` iterated values are truthy.
+*
+* @param iterator - source iterator
+* @param n - minimum number of truthy elements
+* @returns iterator
+*
+* @example
+* var array2iterator = require( '@stdlib/array/to-iterator' );
+*
+* var it = iterCuSome( array2iterator( [ false, false, false, true, true, false ] ), 2 );
+*
+* var v = it.next().value;
+* // returns false
+*
+* v = it.next().value;
+* // returns false
+*
+* v = it.next().value;
+* // returns false
+*
+* v = it.next().value;
+* // returns false
+*
+* v = it.next().value;
+* // returns true
+*
+* v = it.next().value;
+* // returns true
+*
+* // ..
+*/
+declare function iterCuSome( iterator: Iterator, n: number ): Iterator;
+
+
+// EXPORTS //
+
+export = iterCuSome;