键值angular 5打字稿的数据结构

Question

I'm looking for a solution that can replicate a key/value dictionary in Python. I am using Angular 5 typescript for my project and I am new to the datatypes available. I have read a bunch of things online and it seems that because Angular is always changing, there are datatypes that are being depreciated or not supported anymore.

This is what I am trying to accomplish. If anyone can recommend a good resource to look at, I would greatly appreciate that.

Python equivalent

string = "the bump from the sump in the sump for the trump and the bump"


a = {}
for x in string.split():
    if x in a.keys():
        a[x] += 1
    else:
        a[x] = 1
print(a)

for b in a.keys():
    if a[b] > 1 and a[b] < 4:
        print(b)
    if a[b] >= 4:
        print(b)

Answer 1

Your code can be written in TypeScript as below:

let string = "the bump from the sump in the sump for the trump and the bump";

let words = string.split(' ');

let wordCount = words.reduce(((acc, elem) => { 
  acc[elem] = (acc[elem] || 0) + 1; return acc;
}), {});

Object.keys(wordCount).forEach((key) => {
  if (wordCount[key] > 1 && wordCount[key] < 4) {
    console.log(wordCount[key]);
  } else if (wordCount[key] >= 4) {
    console.log(wordCount[key]);
  }
});

Answer 2

You can use ES6 " Map " data type:

Have a look at the article https://medium.com/front-end-hacking/es6-map-vs-object-what-and-when-b80621932373 .