Why would the length of a sentence be useful to know?

[jack9512]

Hi, i have done what the exercise has asked me to and passed it… But why is it relevant?.. like why would i want to know how many letters are in the sentence?

[midlindner]

Seems like a reasonable question. I’ll try to give a reasonable answer. You might be hosting a message board, and have a character limit per post. This forum, for example has a minimum characters per post limit. As you get further along in learning to code, you’ll come to realize that you use the .length property of different objects quite often.

[giga8643187873]

Can the length property only be used to determine the length of a string? Or can it also be used to determine the length of other data types?

[mtf]

It is a property of all objects, though some will never report anything but, undefined.

x = {a:1, b:2, c: 3, d: 4, e: 5}
{a: 1, b: 2, c: 3, d: 4, e: 5}
x.length
undefined

y = Array.from(Object.entries(x))
(5) [Array(2), Array(2), Array(2), Array(2), Array(2)]
0: (2) ["a", 1]
1: (2) ["b", 2]
2: (2) ["c", 3]
3: (2) ["d", 4]
4: (2) ["e", 5]
length: 5         //<<< note the physical property
__proto__: Array(0)
y.length
5
(y.length).length
undefined

Objects that have a length are generally iterable. Strings and arrays are iterable. Numbers, booleans, null, undefined, etc. are not.