使用perl进行文件编辑

Question

我有一个大文件（超过20,000行），其中一些行正在盯着＆＃34; +＆＃34;。它的形式为：

This is a file with many lines
Some lines start with plus
+ line one
+ line two
Some lines do
not start with plus
+ line three
+ line four

我想加入所有以+开头的行与前一行。所以我的输出应该如下：

This is a file with many lines
Some lines start with plus line one line two
Some lines do
not start with plus line three line four

如何使用perl执行此操作？

Answer 1

就地文件编辑，

perl -i -pe 'BEGIN{ $/ ="\n+" } chomp' file