Perl 6 - Starting with the basics - Fruitful subroutines(Return values, compare subroutine)

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 5(Fruitful subroutines)の Return values の Exercise.を取り組んでみる。

Return values の Exercise.

コード(Emacs)

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

sub compare($x, $y) {
    return 1 if $x > $y;
    return 0 if $x == $y;
    -1;
}


for 1..10 -> $x {
    for 1..10 -> $y {
        say "compare($x, $y) -> ", compare($x, $y);
    }
}

入出力結果(Terminal, REPL)

$ ./sample_cmp.pl
compare(1, 1) -> 0
compare(1, 2) -> -1
compare(1, 3) -> -1
compare(1, 4) -> -1
compare(1, 5) -> -1
compare(1, 6) -> -1
compare(1, 7) -> -1
compare(1, 8) -> -1
compare(1, 9) -> -1
compare(1, 10) -> -1
compare(2, 1) -> 1
compare(2, 2) -> 0
compare(2, 3) -> -1
compare(2, 4) -> -1
compare(2, 5) -> -1
compare(2, 6) -> -1
compare(2, 7) -> -1
compare(2, 8) -> -1
compare(2, 9) -> -1
compare(2, 10) -> -1
compare(3, 1) -> 1
compare(3, 2) -> 1
compare(3, 3) -> 0
compare(3, 4) -> -1
compare(3, 5) -> -1
compare(3, 6) -> -1
compare(3, 7) -> -1
compare(3, 8) -> -1
compare(3, 9) -> -1
compare(3, 10) -> -1
compare(4, 1) -> 1
compare(4, 2) -> 1
compare(4, 3) -> 1
compare(4, 4) -> 0
compare(4, 5) -> -1
compare(4, 6) -> -1
compare(4, 7) -> -1
compare(4, 8) -> -1
compare(4, 9) -> -1
compare(4, 10) -> -1
compare(5, 1) -> 1
compare(5, 2) -> 1
compare(5, 3) -> 1
compare(5, 4) -> 1
compare(5, 5) -> 0
compare(5, 6) -> -1
compare(5, 7) -> -1
compare(5, 8) -> -1
compare(5, 9) -> -1
compare(5, 10) -> -1
compare(6, 1) -> 1
compare(6, 2) -> 1
compare(6, 3) -> 1
compare(6, 4) -> 1
compare(6, 5) -> 1
compare(6, 6) -> 0
compare(6, 7) -> -1
compare(6, 8) -> -1
compare(6, 9) -> -1
compare(6, 10) -> -1
compare(7, 1) -> 1
compare(7, 2) -> 1
compare(7, 3) -> 1
compare(7, 4) -> 1
compare(7, 5) -> 1
compare(7, 6) -> 1
compare(7, 7) -> 0
compare(7, 8) -> -1
compare(7, 9) -> -1
compare(7, 10) -> -1
compare(8, 1) -> 1
compare(8, 2) -> 1
compare(8, 3) -> 1
compare(8, 4) -> 1
compare(8, 5) -> 1
compare(8, 6) -> 1
compare(8, 7) -> 1
compare(8, 8) -> 0
compare(8, 9) -> -1
compare(8, 10) -> -1
compare(9, 1) -> 1
compare(9, 2) -> 1
compare(9, 3) -> 1
compare(9, 4) -> 1
compare(9, 5) -> 1
compare(9, 6) -> 1
compare(9, 7) -> 1
compare(9, 8) -> 1
compare(9, 9) -> 0
compare(9, 10) -> -1
compare(10, 1) -> 1
compare(10, 2) -> 1
compare(10, 3) -> 1
compare(10, 4) -> 1
compare(10, 5) -> 1
compare(10, 6) -> 1
compare(10, 7) -> 1
compare(10, 8) -> 1
compare(10, 9) -> 1
compare(10, 10) -> 0
$