time-to-botec

README.md (5634B)

---

 <!--
 
 @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.
 
 -->
 
 # untilEach
 
 > Until a test condition is true, invoke a function for each element in a collection.
 
 <!-- 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 untilEach = require( '@stdlib/utils/until-each' );
 ```
 
 #### untilEach( collection, predicate, fcn\[, thisArg ] )
 
 Invokes a `function` for each element in a `collection` until either a `predicate` function returns `true` or the function has iterated over all `collection` elements.
 
 ```javascript
 function predicate( value ) {
     return ( value !== value );
 }
 
 function log( value, index ) {
     console.log( '%s: %d', index, value );
 }
 
 var arr = [ 1, 2, 3, NaN, 4 ];
 
 untilEach( arr, predicate, log );
 /* =>
     0: 1
     1: 2
     2: 3
 */
 ```
 
 Both the `predicate` function and the `function` to apply are provided three arguments:
 
 -   `value`: collection element
 -   `index`: collection index
 -   `collection`: input collection
 
 Basic support for dynamic collections is provided. Note, however, that index incrementation is monotonically increasing.
 
 ```javascript
 function predicate( value ) {
     return ( value !== value );
 }
 
 function log1( value, index, collection ) {
     console.log( '%s: %d', index, value );
     if ( index === collection.length-1 && collection.length < 10 ) {
         collection.push( index+2 );
     }
 }
 
 var arr = [ 1, 2, 3, 4 ];
 
 untilEach( arr, predicate, log1 );
 /* =>
     0: 1
     1: 2
     2: 3
     3: 4
     4: 5
     5: 6
     6: 7
     7: 8
     8: 9
     9: 10
 */
 
 function log2( value, index, collection ) {
     console.log( '%s: %d', index, value );
     collection.shift();
 }
 
 arr = [ 1, 2, 3, 4 ];
 
 untilEach( arr, predicate, log2 );
 /* =>
     0: 1
     1: 3
 */
 ```
 
 To set the function execution context for the applied function, provide a `thisArg`.
 
 ```javascript
 function predicate( value ) {
     return ( value !== value );
 }
 
 function sum( value ) {
     this.sum += value;
     this.count += 1;
 }
 
 var arr = [ 1, 2, 3, NaN, 4 ];
 
 var context = {
     'sum': 0,
     'count': 0
 };
 
 untilEach( arr, predicate, sum, context );
 
 var mean = context.sum / context.count;
 // returns 2.0
 ```
 
 </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`).
 
 -   The function returns the input `collection`.
 
 -   The function does **not** skip `undefined` elements.
 
     <!-- eslint-disable no-sparse-arrays -->
 
     ```javascript
     function predicate( value ) {
         return ( value !== value );
     }
 
     function log( value, index ) {
         console.log( '%s: %s', index, value );
     }
 
     var arr = [ 1, , , 4 ];
 
     untilEach( arr, predicate, log );
     /* =>
         0: 1
         1: undefined
         2: undefined
         3: 4
     */
     ```
 
 -   The function provides limited support for dynamic collections (i.e., collections whose `length` changes during execution).
 
 </section>
 
 <!-- /.notes -->
 
 <!-- Package usage examples. -->
 
 <section class="examples">
 
 ## Examples
 
 <!-- eslint no-undef: "error" -->
 
 ```javascript
 var isEven = require( '@stdlib/assert/is-even' ).isPrimitive;
 var randu = require( '@stdlib/random/base/randu' );
 var floor = require( '@stdlib/math/base/special/floor' );
 var untilEach = require( '@stdlib/utils/until-each' );
 
 function predicate( value ) {
     return ( value !== value );
 }
 
 function log( value, index, collection ) {
     console.log( '%s: %d', index, value );
     if ( isEven( index ) ) {
         collection.shift();
     } else {
         collection.push( index+1 );
     }
 }
 
 var arr;
 var j;
 var i;
 
 arr = new Array( 100 );
 j = floor( randu()*arr.length );
 for ( i = 0; i < arr.length; i++ ) {
     if ( i === j ) {
         arr[ i ] = NaN;
     } else {
         arr[ i ] = i;
     }
 }
 
 untilEach( arr, predicate, 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 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 -->