我的perl脚本出了什么问题？

Question

下面是我的代码,基本上如果答案是"Y",那么脚本会运行一条消息,如果它是其他东西然后它关闭.

#! usr/bin/perl
print "Do you wish to run Program? [Y/N]:";
$answer = <>;
if($answer == "Y") {
 print "COOOL\n";
} else {
 system "exit"
}

Answer 1

如果你问的话,Perl会告诉你究竟是什么问题.只需在代码中添加"使用警告"即可.

#!/usr/bin/perl
use warnings;

print "Do you wish to run Program? [Y/N]:";
$answer = <>;
if($answer == "Y") {
 print "COOOL\n";
} else {
 system "exit"
}

然后运行它,给出:

$ ./y
Do you wish to run Program? [Y/N]:Y
Argument "Y" isn't numeric in numeric eq (==) at ./y line 6, <> line 1.
Argument "Y\n" isn't numeric in numeric eq (==) at ./y line 6, <> line 1.
COOOL

如果你添加"使用诊断",它会更好.

$ ./y
Do you wish to run Program? [Y/N]:Y
Argument "Y" isn't numeric in numeric eq (==) at ./y line 7, <> line 1 (#1)
    (W numeric) The indicated string was fed as an argument to an operator
    that expected a numeric value instead.  If you're fortunate the message
    will identify which operator was so unfortunate.

Argument "Y\n" isn't numeric in numeric eq (==) at ./y line 7, <> line 1 (#1)
COOOL

如果让Perl帮助您找到错误,Perl中的编程会容易得多.

Answer 2

删除换行符.==是数字相等,你需要的字符串eq.

chomp($answer);
if($answer eq "Y") {