Course of Raku / Essentials / Typed variables / Exercises / Converting user input to a number

Solution: Converting user input to a number

The program can be as simple as this:

Code

my Int $n = prompt 'Enter a number: ';
say $n;

🦋 You can find the source code in the file input-number.raku.

Example

Run it and enter an integer number, either positive or negative:

$ raku exercises/typed-variables/input-number.raku
Enter a number: -42
-42

Comments

As we’ve seen, the return value of prompt is IntStr, which can be assigned to an Int variable with no coercion.

Notice, though, that the program will be terminated with an exception if you enter a string that cannot be converted to an integer number.

Course navigation

← Data type conversion / Converting types with prefix operators   |   Positional data types →