With the help of _.iterators.map() method, we can get the function of the new iterator which will return the value of the unary function which uses the values of the List iterator by using this method.
Syntax:
_.iterators.map(iter, unaryFn)
Return: Return the value from the new iterator function.
In the examples given below we are just showing the implementation part, you can use it anywhere as you want.
Note: To execute the below examples you have to install the underscore-contrib library by using this command prompt we have to execute the following command.
npm install underscore-contrib
Example 1: In this example, we can see that by using _.iterators.map() method, we are able to get the value from the new iterator function which uses the unary function to generate values by using this method.
javascript
// Defining underscore contrib variableconst _ = require('underscore-contrib');const iter = _.iterators.List(["Geek", "for", "Geek"]);function postfixGeek(val) { if (val == "Geek") { return val + "s"; } return val;}const geek = _.iterators.map(iter, postfixGeek);geek();geek(); |
Output :
'Geeks' 'for'
Example 2:
javascript
// Defining underscore contrib variableconst _ = require('underscore-contrib');const iter = _.iterators.List(["A", "ABA", "ABCBA"]);function postfixLength(val) { return val + String(val.length);}const geek = _.iterators.map(iter, postfixLength);geek();geek();geek(); |
Output:
'A1' 'ABA3' 'ABCBA5'
