如何非贪婪地替换一行的多个分隔字符串？

Question

我想从相应格式化的输入字符串生成谜语。

示例输入： Foo was the +first+ to get a drink at +the bar+.

期望的输出： Foo was the _____ to get a drink at ___ ___.

使用任何标准的shell工具，最简单的（在眼睛上）解决方案是什么？

Answer 1

这个awk单行应该可以帮到你：

awk -F'+' -v OFS="" 'NF>2{for(i=2;i<=NF;i+=2)gsub(/\S/,"_",$i)}7'

测试

kent$  awk -F'+' -v OFS="" 'NF>2{for(i=2;i<=NF;i+=2)gsub(/\S/,"_",$i)}7' <<<"Foo was the +first+ to get a drink at +the bar+."
Foo was the _____ to get a drink at ___ ___.

Answer 2

你的“轻松上眼”测试可能会因为这个问题的答案而变得紧张。

的Perl：

$ echo "$str" | perl -pe 's/\+(.*?)\+/ ($new=$1) =~ s{\w}{_}g; $new /eg'
Foo was the _____ to get a drink at ___ ___.

Answer 3

这可行，但特别漂亮：

sed -r ':a;/\+[^+]*\+/!b;s//\n&\n/;h;s/.*\n(.*)\n.*/\1/;s/\+([^+]*)\+/\1/g;s/[^ ]/_/g;G;s/(.*)\n(.*)\n.*\n/\2\1/;ta'

像这样：

$ echo "Foo was the +first+ to get a drink at +the bar+." | sed -r ':a;/\+[^+]*\+/!b;s//\n&\n/;h;s/.*\n(.*)\n.*/\1/;s/\+([^+]*)\+/\1/g;s/[^ ]/_/g;G;s/(.*)\n(.*)\n.*\n/\2\1/;ta'
Foo was the _______ to get a drink at ____ ____.

基本上被盗＆＃39;从这里：https://stackoverflow.com/a/16014707/1061997