Streamlining a complex loop structure within a JavaScript code block

Question

Streamlining a complex loop structure within a JavaScript code block

Within my JS code, I've implemented a function. Here it is:

function getMap(objectList) {
  const objectMap = new Map();
  IDS.foreach(id => {
    const attribute = objectList.find(object => object.getId() === id);
    if (attribute) {
      objectMap.set(id, attribute);
    } else {
      objectMap.set(id, null);
    }
}

This implementation seems to involve a nested loop due to the find method inside the forEach loop. Are there any ways to simplify this nested loop? Alternatively, are there other aspects of this function that could be made more concise?

javascript

Answer 1

Answer №1

If each object has a unique ID, one simple solution is to utilize the getId method for each object. In place of traditional if/else statements, you can opt for the conditional operator.

function generateObjectMap(objectList) {
    const objectsById = new Map(
        objectList.map(object => [object.getId(), object])
    );
    const objectMap = new Map();
    for (const id of IDS) {
        objectMap.set(id, objectsById.get(id) || null);
    }
}

Answer 2

If each object has a unique ID, one simple solution is to utilize the getId method for each object. In place of traditional if/else statements, you can opt for the conditional operator.

function generateObjectMap(objectList) {
    const objectsById = new Map(
        objectList.map(object => [object.getId(), object])
    );
    const objectMap = new Map();
    for (const id of IDS) {
        objectMap.set(id, objectsById.get(id) || null);
    }
}

Answer 3

Answer №2

To ensure all IDs have a corresponding entry in the Map with null values and only add entries to the Map for objects that are present in objectList, you can create an array setup like this and then pass it to the constructor of the Map:

function initializeMap(objectList) {
  return new Map([
    ...IDs.map(id => [id, null]),
    ...objectList.map(object => [object.getId(), object])
  ]);
}

Answer 4

To ensure all IDs have a corresponding entry in the Map with null values and only add entries to the Map for objects that are present in objectList, you can create an array setup like this and then pass it to the constructor of the Map:

function initializeMap(objectList) {
  return new Map([
    ...IDs.map(id => [id, null]),
    ...objectList.map(object => [object.getId(), object])
  ]);
}

Answer 5

Answer №3

One way to incorporate native code is through a simple callback method

const result = (IDS || []).map(function(id, idx, arr) {
    const pos = (objectList || []).findIndex(object => object.getId() === id);
    const output = [];
    output[id] = (pos >= 0 ? objectList[pos] : null);
    return output;
});

Hopefully, this explanation sheds some light on the topic! ;D

Answer 6

One way to incorporate native code is through a simple callback method

const result = (IDS || []).map(function(id, idx, arr) {
    const pos = (objectList || []).findIndex(object => object.getId() === id);
    const output = [];
    output[id] = (pos >= 0 ? objectList[pos] : null);
    return output;
});

Hopefully, this explanation sheds some light on the topic! ;D

Streamlining a complex loop structure within a JavaScript code block

Answer №1

Answer №2

Answer №3

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