Perl - Perl入門(Hello, World!)、置換、正規表現、コマンドの実行、バッククォート

初めてのPerl 第7版
原著: Learning Perl:
Making Easy Things Easy
and Hard Things Possible
楽天ブックス Yahoo!

開発環境

• macOS Mojave - Apple (OS)
• Emacs (Text Editor)
• Windows 10 Pro (OS)
• Strawberry Perl (WindowsのPerlの言語処理系)
• Visual Studio Code (Text Editor)
• Perl 5.28 (プログラミング言語)

初めてのPerl 第7版 (Randal L. Schwartz(著)、brian d foy(著)、Tom Phoenix(著)、近藤 嘉雪(翻訳)、嶋田 健志(翻訳)、オライリージャパン)の1章(Perl入門)、1.6(練習問題)1、2、3の解答を求めてみる。

コード

#!/usr/bin/env perl
use strict;
use warnings;
use v5.28;

say "1.\nHello, world!";

say '3.';

# こちらだとこのプログラムと同様に
# Encode.c: loadable library and perl binaries are mismatched
# (got handshake key 0xdb00080, needed 0xc500080)
# となったから、macOSに標準搭載のperldocを使うように変更
# my @lines = `perldoc -u -f atan2`;
my @lines = `/usr/bin/perldoc -u -f atan2`;
for (@lines) {
    s/\w<([^>]+)>/\U$1/g;
    print;
}

入出力結果(Zsh、PowerShell、Terminal)

% chmod a+x sample1.pl 
% ./sample1.pl 
Perl v5.28.0 required--this is only v5.18.4, stopped at ./sample1.pl line 4.
BEGIN failed--compilation aborted at ./sample1.pl line 4.
% ./sample1.pl 
1.\nHello, world!
3.
Encode.c: loadable library and perl binaries are mismatched (got handshake key 0xdb00080, needed 0xc500080)
% ./sample1.pl
1.
Hello, world!
3.
Encode.c: loadable library and perl binaries are mismatched (got handshake key 0xdb00080, needed 0xc500080)
% ./sample1.pl
Perl v5.24.0 required--this is only v5.18.4, stopped at ./sample1.pl line 4.
BEGIN failed--compilation aborted at ./sample1.pl line 4.
% port installed | grep perl
  ossp-uuid @1.6.2_11+perl5_28 (active)
  perl5 @5.26.1_0+perl5_28 (active)
  perl5.28 @5.28.2_2 (active)
% ./sample1.pl 
1.
Hello, world!
3.
Encode.c: loadable library and perl binaries are mismatched (got handshake key 0xdb00080, needed 0xc500080)
% perldoc -u -f atan2
Encode.c: loadable library and perl binaries are mismatched (got handshake key 0xdb00080, needed 0xc500080)
% /usr/bin/perldoc -u -f atan2
% ./sample1.pl 
1.
Hello, world!
3.
=over 8

=item atan2 Y,X
<ATAN2 <ARCTANGENT <TAN <TANGENT

=for Pod::Functions arctangent of Y/X in the range -PI to PI

Returns the arctangent of Y/X in the range -PI to PI.

OR THE TANGENT OPERATION, YOU MAY USE THE C<MATH::TRIG::TAN
function, or use the familiar relation:

    sub tan { sin($_[0]) / cos($_[0])  }

HE RETURN VALUE FOR C<ATAN2(0,0) is implementation-defined; consult
your atan2(3) manpage for more information.

ORTABILITY ISSUES: L<PERLPORT/ATAN2.

=back
% ./sample1.pl
1.
Hello, world!
3.
=over 8

=item atan2 Y,X
<ATAN2 <ARCTANGENT <TAN <TANGENT

=for Pod::Functions arctangent of Y/X in the range -PI to PI

Returns the arctangent of Y/X in the range -PI to PI.

For the tangent operation, you may use the <MATH::TRIG::TAN
function, or use the familiar relation:

    sub tan { sin($_[0]) / cos($_[0])  }

The return value for <ATAN2(0,0) is implementation-defined; consult
your atan2(3) manpage for more information.

Portability issues: <PERLPORT/ATAN2.

=back
% ./sample1.pl
1.
Hello, world!
3.
=over 8

=item atan2 Y,X
ATAN2 ARCTANGENT TAN TANGENT

=for Pod::Functions arctangent of Y/X in the range -PI to PI

Returns the arctangent of Y/X in the range -PI to PI.

For the tangent operation, you may use the MATH::TRIG::TAN
function, or use the familiar relation:

    sub tan { sin($_[0]) / cos($_[0])  }

The return value for ATAN2(0,0) is implementation-defined; consult
your atan2(3) manpage for more information.

Portability issues: PERLPORT/ATAN2.

=back
% 

「Encode.c: loadable library and perl binaries are mismatched (got handshake key 0xdb00080, needed 0xc500080)」を検索してみたら、過去にcpanを使用てから何か問題が起きたっぽいけど、とりあえず先に進むことに。