We can use different built-in properties to help us understand information about specific collection types, like sets or arrays, in our programs!
For example, we can use .count
to find out how many elements are contained within a set:
setName.count
We learned about using .count
with arrays. .count
returns an Int
value that represents the number of values stored inside of a specified set.
For example, we can create a set to store the items we found in our lunchbox:
var lunchbox: Set = ["Apple", "Sandwich"]
Then, we could use .count
to find out how many items we have in lunchbox
:
print("I have \(lunchbox.count) items in my lunchbox!") // Prints: I have 2 items in my lunchbox!
If we want to find out if our set is empty, we can use the .isEmpty
property to check if there are values contained within our set.
setName.isEmpty
- If there are no values in the set, the expression will return
true
. - If there are values, the expression will return
false
.
Letβs revisit the set instruments
and place instruments.isEmpty
in the conditional of an if
statement:
var instruments = Set<String>() if instruments.isEmpty { print("Let's sign up for piano lessons!") } // Prints: Let's sign up for piano lessons!
Instructions
Create an if
statement in Socks.swift with a conditional that checks if sockDrawer
is empty using .isEmpty
.
Inside the if
statement, print the output "Time to add some more socks!"
.
Underneath the if
statement, create an else
statement.
Inside the body of the else
statement, print the following message:
We have [X] pairs of socks.
Replace [X]
with the number of items in sockDrawer
using .count
.