任何方式来访问运行中的匹配组？ [英] any way to access the matched groups in action?

问题描述

我经常发现自己做同样的比赛中的行动模式，进入输入记录，例如某些部分

I often find myself doing the same match in the action as the pattern, to access some part of the input record, e.g.

/^Compiled from \"(.*)\"$/ {
    file_name = gensub("^Compiled from \"(.*)\"$", "\\1", "g");
    print file_name;
}

所以，正则表达式匹配两次完成。有没有什么办法可以访问 \\\\ 1 中，而无需再次匹配的行动？

So the regexp matching is done twice. Is there any way I can access \\1 in the action without matching again?

我想无论在pattert匹配与额外的code减少。

I am trying to both reduce on pattert matching and extra code.

推荐答案

不幸的是，GAWK，不具有 SED 的结转功能，使用空 // 。

Unfortunately, GAWK, doesn't have the carry-forward feature of sed which uses an empty //.

sed '/\(patt\)ern/ {s//new\1/}' inputfile

不过，你可以庆幸，因为变量最近被发明，它们可以用于这个目的！

However, you can rejoice since variables have recently been invented and they can be used for just this purpose!

BEGIN {
    pattern = "^Compiled from \"(.*)\"$"
}
$0 ~ pattern {
    file_name = gensub(pattern, "\\1", "");
    print file_name;
}

这篇关于任何方式来访问运行中的匹配组？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！