Kotlin contains built-in properties and functions that can be used with its various data types. We’ll be looking at the most common built-in property and function for variables of the String type. You can access the full list in Kotlin’s documentation.
In short, a property provides information on a particular value. Kotlin supports a single String property, length
which returns the number of characters in a String. Let’s see an example:
val tallestMountain = "Mount Everest" print(tallestMountain.length) // Prints: 13
The number of characters in "Mount Everest"
equates to 13
. Notice how the whitespace is also included in the count.
In addition, a String data type also contains built-in functions that can be used to perform certain actions on the String it’s appended on. For example, the capitalize()
function returns a capitalized String:
var name = "codecademy" println(name.capitalize()) // Prints: Codecademy
Note that although the returned value is Codecademy
, the original lowercase String, "codecademy"
, goes unchanged:
println(name) // Prints: codecademy
To persist any changes made by the function, we can reassign the result of name.capitalize()
to name
and update the variable:
name = name.capitalize() println(name) // Prints: Codecademy
Or we can store the result in an entirely new variable:
var capitalizedName = name.capitalize() println(capitalizedName) // Prints: Codecademy
Note: Characters have their own built-in properties and functions in Kotlin. Reference this page in Kotlin’s documentation for a list of all of them.
Instructions
In MaryPoppins.kt, below the initialization of the given variable, reassign the value of word
to the result of word.capitalize()
. Make sure to do this on one line.
On the following line, declare a variable, wordSize
and initialize it with the result of appending the length
property on word
.
Next, use a String template or String concatenation within a print statement to output the following text:
[word] has [wordSize] letters.
Replace the brackets with the correct notation.