Challenge 110

• Program: raku/ch-1.raku

PhoneNumber grammar parses each entry one by one. country-code handles the 3 cases for country codes & number handles the other part.

We just loop over every entry & print it if it's a valid phone number.

grammar PhoneNumber {
    token TOP { \s* <country-code> \s+ <number> }
    token country-code { '+' \d \d | '(' \d \d ')' | \d ** 4 }
    token number { \d ** 10 }
}

for $file.IO.lines -> $entry {
    say $entry if PhoneNumber.parse($entry);
}

• Program: raku/ch-2.raku

.IO.lines part creates a list of lines in the files, then we split it at ",". zip then returns a list which is formatted the way we want it to be.

From the documentation: https://docs.raku.org/routine/zip

Creates a supply that emits combined values as soon as there is a new value seen on all of the supplies.

zip iterates through each of the input lists synchronously, 'Zipping' them together, so that elements are grouped according to their input list index, in the order that the lists are provided.

We then join the entries with ",", loop over the formatted lines & print them.

.say for zip($file.IO.lines.map(*.split(","))).map(*.join(","));