62 lines
2.2 KiB
Markdown
62 lines
2.2 KiB
Markdown
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---
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title: Understand Functional Programming Terminology
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---
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## Understand Functional Programming Terminology
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### Method
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Just as in the last challenge, you must call the `getTea` method and store it in a variable. Only this time, you have 2 variables to store 2 seperate sets of data in. You will see that the `getTea()` function is the same as before, only now it takes in 2 seperate parameters. The first parameter is a function, so we will need to pass in either the `prepareGreenTea()` function or the `prepareBlackTea()` function, followed by the second parameter `numOfCups` which can be input as an integer.
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### Solution
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In this exercise we are assigning the result of a higher order function to variables. To do this we call a function with a callback function as a parameter.
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## Hint:
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```javascript
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const basketOne = makeBasket(addFruit, 10)
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```
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## Solution:
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```javascript
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/**
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* A long process to prepare green tea.
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* @return {string} A cup of green tea.
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**/
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const prepareGreenTea = () => 'greenTea';
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/**
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* Get given number of cups of tea.
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* @param {function():string} prepareTea The type of tea preparing function.
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* @param {number} numOfCups Number of required cups of tea.
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* @return {Array<string>} Given amount of tea cups.
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**/
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const getTea = (prepareTea, numOfCups) => {
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const teaCups = [];
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for(let cups = 1; cups <= numOfCups; cups += 1) {
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const teaCup = prepareTea();
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teaCups.push(teaCup);
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}
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return teaCups;
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};
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// Add your code below this line
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const tea4GreenTeamFCC = getTea(prepareGreenTea,27); // :)
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const tea4BlackTeamFCC = getTea(prepareBlackTea,13); // :)
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// Add your code above this line
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console.log(
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tea4GreenTeamFCC,
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tea4BlackTeamFCC
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);
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```
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## Code explanation:
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In the solution above we passed in the functions ``` prepareGreenTea() ``` and ``` prepareBlackTea() ``` as parameters or callback functions for the ``` getTea() ``` functions being assigned to our two constant variables ``` tea4BlackTeamFCC ```
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and ``` tea4GreenTeamFCC ```.
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This way no global variables are changed, and we have the option to add an unlimited number of different choices of ``` prepareTea() ``` methods since it is a callback function being passed to the higher order function of ``` getTea() ```.
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