A slightly different way to do that: 
perl -pi -e 's/\G\t/  /g' foo.pl

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(Adapted from a "replace-leading-zeros-with-spaces" oneliner I seem to remember)

Update: looks like the original came from merlyn after dominus offered a suggestion similar to japhy's

-Blake

In reply to Re3: The One True Style of indentation: by blakem
in thread The One True Style of indentation: by Petruchio

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