Perl 字符串 - 替换多个字符

Question

I couldn't figure out how to change from /usr/lib to /synopsys/vcs/lib/ by only using $mypath=~s/.....; is there anyway to do it?

$mypath = "/usr/lib";
$mypath =~ s/usr/synopsys/lib//g;

print "$mypath\n";```

Answer 1

the regex replace works like s/match this / replace with this / In perl you need to escape the forward slash / with a back slash \ then use parentheses to capture usr\/ into $1 So for your example:

$mypath =~ s/(usr\/)/$1synopsys\//; 

Answer 2

/ is a special character since it's being used as the delimiter. If therefore needs to be escaped.

$mypath =~ s/\/usr\/lib/\/synopsys\/vcs\/lib\//;

However, using an alternative delimiter means we wouldn't need all those escapes.

$mypath =~ s{/usr/lib}{/synopsys/vcs/lib/};

That replaces the first instance of /usr/lib contained in the string . If you want to replace /usr/lib when it's the entirety of the string, I'd use

$mypath = "/synopsys/vcs/lib/" if $mypath eq "/usr/lib";