Course of Raku / Advanced / Containers / Special and dynamic variables 🆕 / Exercises

The topic variable

Problem

$_ is the topic variable. A for loop sets it to each item in turn, and a method call written with a leading dot and no invocant — like .chars — acts on it, so .chars means $_.chars.

Loop over the three strings 'apple', 'fig', and 'cherry'. For each one, print a line of the form <word> has <n> letters, using the topic $_ for the word and a leading-dot .chars call for its length. Watch how $_ becomes each string in turn.

Example

The program prints:

apple has 5 letters
fig has 3 letters
cherry has 6 letters

Solution

✅ See the solution

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