perl中$word = $&;是什么意思啊？

[cheery_an]

while ($inputline = <STDIN>) {
while ($inputline =~ /\b[A-Z]\S+/g) {
$word = $&;
$word =~ s/[;.,:-]$//; # remove punctuation
for ($count = 1; $count <= @wordlist;
$count++) {
$found = 0;
if ($wordlist[$count-1] eq $word) {
$found = 1;
$wordcount[$count-1] += 1;
last;
}
}
if ($found == 0) {
$oldlength = @wordlist;
$wordlist[$oldlength] = $word;
$wordcount[$oldlength] = 1;
}
}
}
$word = $&;是什么意思？

[cheery_an]

在模式匹配后调用重用部分的结果可用变量$n，全部的结果用变量$&。

[Aylazhang]

参考：http://perldoc.perl.org/perlvar.html

[whatsouta]

man perlvar

[staff]

$inputline =~ /\b[A-Z]\S+/g)

上面的正则表达式匹配到的内容。

[fengjc49]

$& The string matched by the last successful pattern match (not
counting any matches hidden within a BLOCK or eval() enclosed
by the current BLOCK). (Mnemonic: like & in some editors.)
This variable is read-only and dynamically scoped to the
current BLOCK.

The use of this variable anywhere in a program imposes a
considerable performance penalty on all regular expression
matches. See the BUGS manpage.