markdown 使用ruby代替grep / awk / sed就像perl一样

Posted 2021-05-05

With options `-e`, `-n`, `-p`, perl can do what grep/awk/sed can, what about ruby?

Let's take the result of `ls -l` as input and process it with ruby

### grep with ruby
`\ls -l | ruby -ne 'print if /^d/'`

### awk with ruby
`\ls -l | ruby -ne 'puts split(/\s+/).last if /^d/'`

### sed with ruby
`\ls -l | ruby -pe 'gsub /.*\s+(\S+)$/, %q|\1|'`  
`\ls -l | ruby -pe 'gsub(/.*\s+(\S+)$/) {$1.capitalize}'`