[RFC]: add @stdlib/array/base/cusome-by

[kgryte]

Description

This RFC proposes adding the package @stdlib/array/base/cusome-by, which cumulatively tests whether at least n array elements in a provided array passes a test implemented by a predicate function. The function should return a new generic array. The package should also provide an #assign API for setting output values in a provided output array.

function isPositive( value ) {
	return ( value > 0 );
}

var x = [ 0, 0, 0, 1, 1 ];

var y1 = cusomeBy( x, 2, isPositive );
// returns [ false, false, false, false, true ]

var y2 = [ false, null, false, null, false, null, false, null, false, null ];
var out = cusomeBy.assign( x, 2, y2, 2, 0, isPositive );
// returns [ false, null, false, null, false, null, false, null, true, null ]

var bool = ( out === y2 );
// returns true

where the assign API supports an offset and stride (see, e.g., @stdlib/array/base/take).

Both APIs should support accessor arrays (see, e.g., @stdlib/array/base/take).

Related Issues

No.

Questions

No.

Other

• See also @stdlib/utils/some-by

Checklist

• I have read and understood the Code of Conduct.
• Searched for existing issues and pull requests.
• The issue name begins with RFC:.

[stdlib-bot]

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