'ed' is perfect for scripting a series of edits on a bunch of files where sed or awk or perl would be too arcane or bloated (or you've forgotten the exact sed or awk or perl syntax). Quick'n'dirty but it gets the job done, emphasis on quick.
21 of the Best Free Linux Text Editors (LinuxLinks)
Posted Aug 28, 2008 0:37 UTC (Thu) by flewellyn (subscriber, #5047)
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I'm more proficient with sed than ed, myself. I find it very useful, though.
21 of the Best Free Linux Text Editors (LinuxLinks)
Posted Aug 29, 2008 9:17 UTC (Fri) by branden (guest, #7029)
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ed is a more appropriate tool than sed for noninteractive editing when the file to be manipulated is free-form and/or you need to go backwards.
I wouldn't rule anything as beyond sed's capabilities, since thanks to its hold buffer, label and branching features, it's probably Turing-complete. But I think ed is a better (and more idiomatic) fit for the scenarios I mentioned.