Skip to main content
Unix & Linux

Return to Answer

more examples
Source Link
thrig
thrig
  • 35.8k
  • 4
  • 70
  • 88

Generally Perl expressions are chained together with ; so s/.../foo/;s/.../bar/;... for a rename style chaining that operates on the implicit $_ variable. I'm not sure where you got prename from so I'll use my own version of rename here. Probably it is pretty similar to yours. The -p flag is to preview, or to prevent damage to the filesystem.

$ touch 'Something (0482) - a123b456 - Something [00xcf bxc v32 Something].demo' $ rename -p 's/(^.*)/\L\1/;s/\(.*?\)|_//gs;s/\[.*?\]|_//gs;s/ /_/g' *.demo rename Something (0482) - a123b456 - Something [00xcf bxc v32 Something].demo something__-_a123b456_-_something_.demo

However this can probably be improved; there is no reason to use regular expressions for everything here.

$ rename -p '$_=lc; s/\(.*?\)|_//gs;s/\[.*?\]|_//gs; tr/ /_/' *.demo rename Something (0482) - a123b456 - Something [00xcf bxc v32 Something].demo something__-_a123b456_-_something_.demo

So instead we use $_=lc to lowercase everything in $_, and replace the s/ /_/ with a tr. Or maybe instead runs of white space should be replaced with a single underscore? If so, s/\s+/_/g. The () and [] can probably also be improved on, though that gets more complicated to properly match on such balanced expressions.

On additional study s/\(.*?\)|_//gs does not make much sense; there are better ways to kill off _ characters without that (repeated!) alternation in the () and [] killing expressions, so:

$ rename -p '$_=lc; tr/_//; s/\(.*?\)//gs;s/\[.*?\]//gs; tr/ /_/' *.demo rename Something (0482) - a123b456 - Something [00xcf bxc v32 Something].demo something__-_a123b456_-_something_.demo

The .*? could probably be made more efficient by using something like s/\([^)]*\)//gs to match only-that-which-is-not-the-closing-character but you probably want readability more than efficiency here. But if you are using regular expressions in one-liners you've already blown your readability budget.

$ rename -p '$_=lc; tr/_//; s/\([^)]*\)//g; s/\[[^\]]*\]//g; tr/ /_/' *.demo rename Something (0482) - a123b456 - Something [00xcf bxc v32 Something].demo something__-_a123b456_-_something_.demo

Generally Perl expressions are chained together with ; so s/.../foo/;s/.../bar/;... for a rename style chaining that operates on the implicit $_ variable. I'm not sure where you got prename from so I'll use my own version of rename here. Probably it is pretty similar to yours. The -p flag is to preview, or to prevent damage to the filesystem.

$ touch 'Something (0482) - a123b456 - Something [00xcf bxc v32 Something].demo' $ rename -p 's/(^.*)/\L\1/;s/\(.*?\)|_//gs;s/\[.*?\]|_//gs;s/ /_/g' *.demo rename Something (0482) - a123b456 - Something [00xcf bxc v32 Something].demo something__-_a123b456_-_something_.demo

However this can probably be improved; there is no reason to use regular expressions for everything here.

$ rename -p '$_=lc; s/\(.*?\)|_//gs;s/\[.*?\]|_//gs; tr/ /_/' *.demo rename Something (0482) - a123b456 - Something [00xcf bxc v32 Something].demo something__-_a123b456_-_something_.demo

So instead we use $_=lc to lowercase everything in $_, and replace the s/ /_/ with a tr. Or maybe instead runs of white space should be replaced with a single underscore? If so, s/\s+/_/g. The () and [] can probably also be improved on, though that gets more complicated to properly match on such balanced expressions.

Generally Perl expressions are chained together with ; so s/.../foo/;s/.../bar/;... for a rename style chaining that operates on the implicit $_ variable. I'm not sure where you got prename from so I'll use my own version of rename here. Probably it is pretty similar to yours. The -p flag is to preview, or to prevent damage to the filesystem.

$ touch 'Something (0482) - a123b456 - Something [00xcf bxc v32 Something].demo' $ rename -p 's/(^.*)/\L\1/;s/\(.*?\)|_//gs;s/\[.*?\]|_//gs;s/ /_/g' *.demo rename Something (0482) - a123b456 - Something [00xcf bxc v32 Something].demo something__-_a123b456_-_something_.demo

However this can probably be improved; there is no reason to use regular expressions for everything here.

$ rename -p '$_=lc; s/\(.*?\)|_//gs;s/\[.*?\]|_//gs; tr/ /_/' *.demo rename Something (0482) - a123b456 - Something [00xcf bxc v32 Something].demo something__-_a123b456_-_something_.demo

So instead we use $_=lc to lowercase everything in $_, and replace the s/ /_/ with a tr. Or maybe instead runs of white space should be replaced with a single underscore? If so, s/\s+/_/g. The () and [] can probably also be improved on, though that gets more complicated to properly match on such balanced expressions.

On additional study s/\(.*?\)|_//gs does not make much sense; there are better ways to kill off _ characters without that (repeated!) alternation in the () and [] killing expressions, so:

$ rename -p '$_=lc; tr/_//; s/\(.*?\)//gs;s/\[.*?\]//gs; tr/ /_/' *.demo rename Something (0482) - a123b456 - Something [00xcf bxc v32 Something].demo something__-_a123b456_-_something_.demo

The .*? could probably be made more efficient by using something like s/\([^)]*\)//gs to match only-that-which-is-not-the-closing-character but you probably want readability more than efficiency here. But if you are using regular expressions in one-liners you've already blown your readability budget.

$ rename -p '$_=lc; tr/_//; s/\([^)]*\)//g; s/\[[^\]]*\]//g; tr/ /_/' *.demo rename Something (0482) - a123b456 - Something [00xcf bxc v32 Something].demo something__-_a123b456_-_something_.demo
Source Link
thrig
thrig
  • 35.8k
  • 4
  • 70
  • 88

Generally Perl expressions are chained together with ; so s/.../foo/;s/.../bar/;... for a rename style chaining that operates on the implicit $_ variable. I'm not sure where you got prename from so I'll use my own version of rename here. Probably it is pretty similar to yours. The -p flag is to preview, or to prevent damage to the filesystem.

$ touch 'Something (0482) - a123b456 - Something [00xcf bxc v32 Something].demo' $ rename -p 's/(^.*)/\L\1/;s/\(.*?\)|_//gs;s/\[.*?\]|_//gs;s/ /_/g' *.demo rename Something (0482) - a123b456 - Something [00xcf bxc v32 Something].demo something__-_a123b456_-_something_.demo

However this can probably be improved; there is no reason to use regular expressions for everything here.

$ rename -p '$_=lc; s/\(.*?\)|_//gs;s/\[.*?\]|_//gs; tr/ /_/' *.demo rename Something (0482) - a123b456 - Something [00xcf bxc v32 Something].demo something__-_a123b456_-_something_.demo

So instead we use $_=lc to lowercase everything in $_, and replace the s/ /_/ with a tr. Or maybe instead runs of white space should be replaced with a single underscore? If so, s/\s+/_/g. The () and [] can probably also be improved on, though that gets more complicated to properly match on such balanced expressions.