perl - 如何在 Perl 中从终端获取输入

Question

我正在创建一个简单的聊天机器人程序，如 ELIZA .
我正在从终端接受问题并通过对话框发送回复，但我的程序只接受第一个输入并重复。
例如，当我运行我的脚本时，输出可能是这样的:

[Eliza]: Hi, I'm a psychotherapist. What is your name?
user Input: hello my name is adam.
[Eliza]: hello adam, how are you?
[Eliza]: your name is adam
[Eliza]: your name is adam
[Eliza]: your name is adam
[Eliza]: your name is adam
[Eliza]: your name is adam

它无休止地重复。
我不知道我哪里做错了。如何让我的程序从键盘读取下一行？

sub hello {
    print "[Eliza]: Hi, I'm a psychotherapist. What is your name? \n";
}


sub getPatientName {
    my ($reply) = @_;

    my @responses = ( "my name is", "i'm", "i am", "my name's" );

    foreach my $response ( @responses ) {

        if ( lc($reply) =~ /$response/ ) {
            return  "$'";
        }
    }

    return lc($reply);
}

sub makeQuestion {
    my ($patient) = @_;

    my %reflections = (
        "am"    =>   "are",
        "was"   =>   "were",
        "i"     =>   "you",
        "i'd"   =>   "you would",
        "i've"  =>   "you have",
        "i'll"  =>   "you will",
        "my"    =>   "your",
        "are"   =>   "am",
        "you've"=>   "I have",
        "you'll"=>   "I will",
        "your"  =>   "my",
        "yours" =>   "mine",
        "you"   =>   "me",
        "me"    =>   "you"
    );

    if ( $count == 0 ) {
        $patientName = getPatientName($patient);
        $count += 1;
        print "Hello $patientName , How are you? \n";
    }

    my @toBes = keys %reflections;

    foreach my $toBe (@toBes) {

        if ($patient =~/$toBe/) {
            $patient=~ s/$toBe/$reflections{$toBe}/i;
            print "$patient? \n";
        }
    }
}

sub eliza {

    hello();

    my $answer = <STDIN>;

    while ($answer) {
        chomp $answer;
        #remove . ! ;
        $answer =~ s/[.!,;]/ /;
        makeQuestion($answer);
    }
}

eliza();

Answer 1

您的 while循环从不读取输入。 $answer得到 STDIN在循环之前，大概有一个字符串，在 while 中计算为真健康)状况。循环中的正则表达式不能改变这一点。

因此不仅没有新的输入分配给 $answer ，但在第一次迭代之后，循环中没有任何变化。所以它永远运行，打印基于相同的问题 $answer .

你需要

while (my $answer = <STDIN>) {
    chomp $answer;
    # ...
}

反而。

每次情况 while (...)评估新输入通过 <STDIN> 读取并分配给 $answer .然后每个新问题使用新的 $answer .请注意如何在 while 中声明变量条件所以只存在于循环体内(以及在其声明之后的条件中)。这是将其范围限制在循环内需要的地方的好方法。

文件句柄读取 <...>返回 undef当它得到时 EOF (或出错)并且循环终止。见 I/O Operators in perlop .终端用户通常可以通过 Ctrl-d 实现这一点。 .