Related
I have the following nested array of objects:
const data = [
{
product: {
id: "U2NlbmFyaW9Qcm9swkdWN0OjEsz",
currentValue: 34300,
},
task: {
id: "R2VuZXJpY1Byb2R1Y3Q6MTA",
name: "My Annuity",
},
instrumentDetails: [
{
instrument: {
id: "U2NlbmFyaW9JbnN0cnVtZW50OjEz",
supplier: {
id: "U3VwcGxpZXJJbnN0cnVtZW50OjUzNjQ",
supplierDetails: {
name: "Local - Class A",
},
},
currentValue: 44323,
},
assets: {
current: 1.2999270432626702,
fixed: 0.5144729302004819,
financial: 0.0723506386331588,
cash: 0.00006003594786398524,
alternative: 0.05214078143244779,
property: 0.548494862567579,
local: 0.10089348539739094,
global: 0,
},
},
],
},
{
product: {
id: "U2NlbmFyaW9Qcm9swkfefewdWN0OjEsz",
currentValue: 3435300,
},
task: {
id: "R2VuZXJpYfewfew1Byb2R1Y3Q6MTA",
name: "Living",
},
instrumentDetails: [
{
instrument: {
id: "U2NlbmFyadewwW9JbnN0cnVtZW50OjEz",
supplier: {
id: "U3VwcGxpZdwdwXJJbnN0cnVtZW50OjUzNjQ",
supplierDetails: {
name: "Local - Class B",
},
},
currentValue: 434323,
},
assets: {
current: 1.294353242,
fixed: 0.514434242004819,
financial: 0.07434286331588,
cash: 0.0000434398524,
alternative: 0.05242348143244779,
property: 0.543242567579,
local: 0.100432439739094,
global: 0,
},
},
],
},
];
The above data presents an array of products which consist of instruments that are described in instrumentDetails array. I am trying to find an instrument by supplier id and update its assets by multiplying all of the asset values by a given number.
Here is my function:
export const updateObject = (
productsArr: any,
supplierInstrumentId: string
) => {
return productsArr.map(
(product: any) => {
product.instrumentDetails.map(
(instrumentDetail: any) => {
if (
instrumentDetail.instrument.supplier.id ===
supplierInstrumentId
) {
instrumentDetail.assets.current = instrumentDetail.assets.current + 5;
instrumentDetail.assets.fixed= instrumentDetail.assets.fixed+ 5;
instrumentDetail.assets.financial= instrumentDetail.assets.financial+ 5;
instrumentDetail.assets.cash= instrumentDetail.assets.cash+ 5;
}
}
);
}
);
};
This function is giving an error :
Uncaught TypeError: Cannot assign to read only property 'current' of
object '#'
How can I deeply update the above data? Please help.
You need to return a new instrumentDetail-type object from the map function. Don't try to update the existing object.
(instrumentDetail: any) => {
const assets = instrumentDetail.instrument.supplier.id === supplierInstrumentId
? Object.fromEntries(
Object.entries(instrumentDetail.assets).map(([k, v]) => [k, v + 5])
)
:
instrumentDetail.assets;
return {
...instrumentDetail,
assets
};
}
Your product map is not returning which is why you're likely getting an undefined. I wasn't getting the typescript error which you mentioned above. This should leave the array in the state at which you intended.
const updateObject = (
productsArr: any,
supplierInstrumentId: string
) => {
return productsArr.map(
(product: any) => {
product.instrumentDetails.map(
(instrumentDetail: any) => {
if (
instrumentDetail.instrument.supplier.id ===
supplierInstrumentId
) {
instrumentDetail.assets.current += 5;
instrumentDetail.assets.fixed= instrumentDetail.assets.fixed+ 5;
instrumentDetail.assets.financial= instrumentDetail.assets.financial+ 5;
instrumentDetail.assets.cash= instrumentDetail.assets.cash+ 5;
return instrumentDetail;
}
}
);
return product;
}
);
};
How can i have the last item on the list where the case it is success?
children: [
{
case: "no-success",
name: "bruno",
endOffset: 5
},
{
case: "no-success",
name: "pippo",
endOffset: 5
}
{
case: "success",
name: "jo",
endOffset: 5
},
{
case: "success",
name: "Matteo",
endOffset: 5
},
{
case: "np-success",
name: "Robert",
endOffset: 5
}
]
I need to have the item where the name is Matteo.
Example for have the first i do : var foundIdx = this.newListWords[i].children.find(item => item.case === 'success').
Definition:
The find() method returns the FIRST element in the provided array that
satisfies the provided testing function. If no values satisfy the
testing function, undefined is returned.
You can reverse array:
this.newListWords[i].children.reverse().find(item => item.case === 'success')
Or you can use filter and get last child
const filtered = this.newListWords[i].children.filter(item => item.case === 'success')
const lastFind = filtered[filtered.length-1]
function lastSuccess(list: any[]): any {
const SUCCESS_STRING = 'success';
const [lastItem] = list // Take the list's head
.filter(o => o.success === SUCCESS_STRING) // Filter for success
.reverse(); // Reverse the list
return lastItem;
}
const item = lastSuccess(this.newListWords[i].children);
var children = [
{
case: "no-success",
name: "bruno",
endOffset: 5
},
{
case: "no-success",
name: "pippo",
endOffset: 5
},
{
case: "success",
name: "jo",
endOffset: 5
},
{
case: "success",
name: "Matteo",
endOffset: 5
},
{
case: "np-success",
name: "Robert",
endOffset: 5
}
];
function getLastSuccess(children) {
if (!Array.isArray(children)) {
return {};
}
for (var i = children.length - 1, o; o = children[i]; i--) {
if (o.case === 'success') {
return o;
}
}
}
console.log(getLastSuccess(children));
Single line code
let v = children.reduce((s, c) => { if (c.case === "success") { return c } else { return s } }, null);
You will get null if there is no success.
This should find the last item in the filtered array with 'success',
children.findLast(item => item.case === 'success')
I have an array of objects, I need to delete a complete object based on the id
Input :
filters: [
{
key: "status",
label: "En attente",
value: "waiting",
id: 0
},
{
key: "dateDue[min]",
label: "15/12/2019",
value: "15/12/2019",
id: 1
},
{
key: "dateDue[max]",
label: "02/02/2020",
value: "02/02/2020",
id: 2
},
{
key: "bien",
values: [
{
label: "Studio Bordeaux",
value: 36,
id: 3
},
{
label: "Studio 2",
value: 34,
id: 184
}
]
},
{
key: "type",
values: [
{
type: "receipts",
label: "Loyer",
value: "loyer",
id: 4
},
{
type: "receipts",
label: "APL",
value: "apl",
id: 5
},
{
type: "spending",
label: "taxes",
value: "taxes",
id: 6
}
]
}
]
So I created a removeItem method with the id that must be deleted in parameters
removeItem method :
removeItem = (e, id) => {
const { filters } = this.state;
const remove = _.reject(filters, el => {
if (!_.isEmpty(el.values)) {
return el.values.find(o => o.id === id);
}
if (_.isEmpty(el.values)) {
return el.id === id;
}
});
this.setState({
filters: remove
});
};
I use lodash to make my job easier and more specifically _.reject
My issue is the following :
I manage to correctly delete the classic objects for example
{
key: "status",
label: "En attente",
value: "waiting",
id: 0
}
but my method however does not work for objects of the following form
{
key: "bien",
values: [
{
label: "Studio Bordeaux",
value: 36,
id: 3
},
{
label: "Studio 2",
value: 34,
id: 184
}
]
},
currently the whole object is deleted and not only the object in the values array according to its id
Here is my codesandbox!
thank you in advance for your help
EDIT
I found a solution with lodash (compact), I share my solution here :
removeIdFromCollection = id => {
const { filters } = this.state;
const newFilters = [];
_.map(filters, filter => {
if (filter.values) {
const valuesTmp = _.compact(
_.map(filter.values, value => {
if (value.id !== id) return value;
})
);
if (!_.isEmpty(valuesTmp)) {
return newFilters.push({
key: filter.key,
values: valuesTmp
});
}
}
if (filter.id && filter.id !== id) return newFilters.push(filter);
});
return newFilters;
};
removeItem = id => e =>
this.setState({
filters: this.removeIdFromCollection(id)
});
The values false, null, 0, "", undefined, and NaN are removed with lodash compact (_.compact(array))
Here is my updated codesandbox
You will need to filter the filters array and each values separately. Below is a recursive function which will remove items with the given id from the filters array and from the values property.
PS. This example is not using Lodash as I think it is not needed in this case.
removeIdFromCollection = (collection, id) => {
return collection.filter(datum => {
if (Array.isArray(datum.values)) {
datum.values = this.removeIdFromCollection(datum.values, id);
}
return datum.id !== id;
});
}
removeItem = (e, id) => {
const { filters } = this.state;
this.setState({
filters: this.removeIdFromCollection(filters, id),
});
};
The problem would be the structure of the object. You'll need to refactor for that inconvenient array out of nowhere for uniformity:
// Example
filters: [
...
{
key: "type",
values: [
{
type: "receipts",
label: "Loyer",
value: "loyer",
id: 4
},
...
]
...
}
// could be
filters: [
...
{
key: "type-receipts",
label: "Loyer",
value: "loyer",
id: 4
}
...
]
Repeat the pattern on all of it so you could just use the native array filter like this:
const newFilters = filters.filter(v => v.id !== id);
this.setState({
filters: newFilters,
});
I found a solution with lodash, I share it with you here :
removeIdFromCollection = id => {
const { filters } = this.state;
const newFilters = [];
_.map(filters, filter => {
if (filter.values) {
const valuesTmp = _.compact(
_.map(filter.values, value => {
if (value.id !== id) return value;
})
);
if (!_.isEmpty(valuesTmp)) {
return newFilters.push({
key: filter.key,
values: valuesTmp
});
}
}
if (filter.id && filter.id !== id) return newFilters.push(filter);
});
return newFilters;
};
removeItem = id => e =>
this.setState({
filters: this.removeIdFromCollection(id)
});
Here is my updated codesandbox
I have the following array:
[
{
id: 1
},
{
id: 2
},
{
id: 3
},
{
id: 4
}
]
Every 5 seconds my application receives a new array and I need to compare the difference between the next one...
So the next array is:
[
{
conversation_id: 1
},
{
conversation_id: 2
},
{
conversation_id: 4
}
]
Considering that identity is different. How can I compare with the previous and get an array with the excluded item?
[
{
id: 3
}
]
Use _.differenceWith():
const prev = [{"id":1},{"id":2},{"id":3},{"id":4}]
const next = [{"conversation_id":1},{"conversation_id":2},{"conversation_id":4}]
const diff = _.differenceWith(prev, next, ({ id }, { conversation_id }) => _.eq(id, conversation_id))
console.log(diff)
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.10/lodash.js"></script>
I think you can use mix of javascript and lodash to solve this problem.
var arrayList = [
{
id: 1
},
{
id: 2
},
{
id: 3
},
{
id: 4
}
];
var conv_array = [
{
conversation_id: 1
},
{
conversation_id: 2
},
{
conversation_id: 4
}
];
var itemsNotInArray = [];
arrayList.filter(function (item) {
if (!_.find(conv_array, {conversation_id: item.id })) {
console.log("not in array", item);
itemsNotInArray.push(item);
}
});
console.log("result you expected", itemsNotInArray);
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.11/lodash.min.js"></script>
Filter the first array and compare each value till you find a missing id :
var array1 = [{
id: 1
},
{
id: 2
},
{
id: 3
},
{
id: 4
}
];
var array2 = [{
conversation_id: 1
},
{
conversation_id: 2
},
{
conversation_id: 4
}
];
var test = array1.filter(
conv => !array2.find(
id => id.conversation_id === conv.id
)
);
console.log(test)
From lodash documentation, the third argument to differenceBy is
[iteratee=_.identity] (Function): The iteratee invoked per element.
Based on this, you can use
var current = [
{
id: 1
},
{
id: 2
},
{
id: 3
},
{
id: 4
}
];
and
var next = [
{
conversation_id: 1
},
{
conversation_id: 2
},
{
conversation_id: 4
}
];
then
var difference = _.differenceBy(current, next, function(obj) {
return obj.id || obj.conversation_id;
});
Or shortened with an arrow function:
var difference = _.differenceBy(current, next, (x) => x.id || x.conversation_id)
I've got some data that came from classy service in Angular that looks like this (briefly):
const obj = {
field: [
{
id: 1,
items: []
},
{
id: 2,
items: [ { wateva: 'wateva1' } ]
},
{
id: 3,
items: false
},
{
id: 4,
items: [ { yeah: 7 } ]
}
]
}
Well, my task is just to collect all array items, that are not empty.
My solution (actually my solution is written in TypeScript and Angular 5, but here to make it more simple and comprehensible it's going to be like...) :
function getItems() {
const items = [];
obj.field.forEach(currentField => {
if (currentField.items && currentField.items.length) {
currentField.items.forEach(currentItem => items.push(currentItem));
}
});
return items;
}
Right, it's dead simple and it works as expected (current one will return...) :
[ { wateva: 'wateva1' }, { yeah: 7 } ]
And now my question... How to make my solution functional? I want to get rid of my new variable items, I don't want to push in that variable, I just want to return the result in one action. Any help will be appreciated.
P.S. Suggestions with 3rd libraries are not accepted :)
If you can use es6 (and since you mentioned you're using typescript, that should be fine), you can turn this into a nice functional one-liner by combining concat, map, filter, and the spread operator:
const obj = {
field: [
{
id: 1,
items: []
},
{
id: 2,
items: [ { wateva: 'wateva1' } ]
},
{
id: 3,
items: false
},
{
id: 4,
items: [ { yeah: 7 } ]
}
]
}
function getItems(obj) {
return [].concat(...obj.field.map(o => o.items).filter(Array.isArray))
}
console.log(getItems(obj))
You can use flatMap (stage 3). flatMap here matches Fantasy Land's spec for chain.
data.field.flatMap
(({ items }) =>
Array.isArray (items) ? items : []
)
// [ { wateva: 'wateva1' }, { yeah: 7 } ]
You can polyfill it in environments that don't have it
Array.prototype.flatMap = function (f) {
return this.reduce
( (acc, x) =>
acc.concat (f (x))
, []
)
}
Full program demonstration
Array.prototype.flatMap = function (f) {
return this.reduce
( (acc, x) =>
acc.concat (f (x))
, []
)
}
const data =
{ field:
[ { id: 1, items: [] }
, { id: 2, items: [ { wateva: 'wateva1' } ] }
, { id: 3, items: false }
, { id: 4, items: [ { yeah: 7 } ] }
]
}
const result =
data.field.flatMap
(({ items }) =>
Array.isArray (items) ? items : []
)
console.log (result)
// [ { wateva: 'wateva1' }, { yeah: 7 } ]
You can use Array.reduce and the spread operator to accumulate onto an empty array:
obj.field.reduce(
(acc, current) => current.items && current.items.length > 0 ? [...acc, ...current.items] : acc, [])
);
Using Array.prototype.reduce, object destructuring, and spread assignments:
function getItems({ field }) {
return field.reduce((result, { items }) =>
items instanceof Array ?
items.reduce((items, item) => [...items, item], result) :
result
, []);
}