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Update toHash.md

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Angelos Chalaris
2018-05-31 21:09:51 +03:00
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parent 8ff17839b9
commit aa9e98fa85
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snippets/toHash.md
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@ -1,8 +1,8 @@
### toHash
Reduces a given Array Like into a value hash(keyed data store)
Reduces a given Array-like into a value hash (keyed data store).
Given an Iterable or Array like structure we call Array.prototype.reduce.call on the provided object to step over it and return an Object keyed by the reference value
Given an Iterable or Array-like structure, call `Array.prototype.reduce.call()` on the provided object to step over it and return an Object, keyed by the reference value.
```js
const toHash = ( object, key ) =>
@ -12,11 +12,10 @@ const toHash = ( object, key ) =>
```js
toHash([ 4,3,2,1 ]); // { 0: 4, 1: 3, 2: 2, 1: 1 }
toHash([ { a: 'label' } ], 'a'); // { label: { a: 'label' } }
// A more in depth example
// A more in depth example:
let users = [ { id: 1, first: 'Jon' }, { id: 2, first: 'Joe' }, { id: 3, first: 'Moe' } ];
let managers = [ { manager: 1, employees: [ 2, 3 ] } ];
// We use function here because we want a bindable reference but a closure referencing the hash would work too
// We use function here because we want a bindable reference, but a closure referencing the hash would work, too.
managers.forEach( manager =>
manager.employees = manager.employees.map(
function( id ){
@ -25,5 +24,5 @@ managers.forEach( manager =>
toHash( users, 'id' )
)
);
managers // [ { manager:1, employees: [ { id: 2, first: "Joe" }, { id: 3, first: "Moe" } ] } ]
managers; // [ { manager:1, employees: [ { id: 2, first: "Joe" }, { id: 3, first: "Moe" } ] } ]
```