Question

为什么＃字符被视为＆＃39;字＆＃39; Perl中的角色？或者我误解了这段代码应该如何工作？

#!/usr/bin/perl

my $filename = "Something_with_#_sign.jpg";

$filename =~ s/        # substitute...
                [^             # characters which are NOT:
                \w                # "word" characters
                ]              # end of character classes
                /_/xg;     # ...with an underscore

print "$filename\n";

收率：

Something_with_#_sign.jpg

我原本预计＃符号会被_（下划线）替换。

Answer 1

/x不会修改字符类（或\x20或s{3,4}等）的语法，所以

[^             # characters which are NOT:
\w                # "word" characters
]              # end of character classes

是一种奇怪的写作方式

[^ "#:NOTacdefhilnorst\n\w]

为什么＃字符被视为＆＃39;字＆＃39; Perl中的角色？

1 个答案: