Perl 6 - Starting with the basics - Case study: word play(lipogram, e, Reading word lists, String, index, Nil, ===)

Think Perl 6

開発環境

• macOS Sierra - Apple (OS)
• Emacs (Text Editor)
• Perl 6 (プログラミング言語)
• Rakudo(コンパイラ、実装)

Think Perl 6: How to Think Like a Computer Scientist (Laurent Rosenfeld(著)、Allen B. Downey(著)、Oreilly & Associates Inc)のPart 1(Starting with the basics)、Chapter 8(Case study: word play)の Exercises 8-2.を取り組んでみる。

Exercises 8-2.

コード(Emacs)

#!/usr/bin/env perl6
# -*- coding: utf-8 -*-

sub has-no-e($word) {
    $word.index('e') === Nil;
}

my $total = 0;
my $has-no-e-words = 0;
for 'words.txt'.IO.lines {
    $total += 1;
    if has-no-e($_) {
        $has-no-e-words += 1;
    }
}

say $has-no-e-words / $total * 100, '%';

入出力結果(Terminal, REPL)

$ ./sample2.pl
33.0738342%
$