.map(callback)

Description

Map takes in an array as its input and then does something to each item, defined by a custom callback function. Inline or Functions.

Parameters

Map needs the array to modify, and the custom function that tells it how to modify the items.

Usage On Arrays

In the provided examples, the map function is being used to iterate over the array num, which contains the numbers [1,2,3,4,5]. For each element in the array, the map function applies a specified operation, defined by the callback function, to transform the elements.

• A separate function myfunc is defined using the syntax def myfunc(this.item).

• Inside the function, this.item * 2 is returned, which multiplies each item by 2.

• num.map(myfunc) is called, applying the myfunc to each element, resulting in a new array [2,4,6,8,10]

num = [1,2,3,4,5]

def myfunc(this.item) (
  return this.item * 2
)

log num.map(myfunc)
// [2,4,6,8,10]

Using map with arrow functions or lambda functions can simplify your code, especially for straightforward transformations. This method is particularly useful when:

• The operation is a simple one-liner.

• The function doesn't need to be reused elsewhere.

• Improved readability and conciseness are desired.

In more complex scenarios, you might still prefer defining a separate function for clarity and potential reuse. Nonetheless, for many use cases involving array transformations, arrow functions offer a neat and efficient approach.

num = [1,2,3,4,5]

log num.map(def(this.item) -> (
  return this.item * 2
))
// [2,4,6,8,10]