uniq without pre-sorting

perl -ne 'print if !$a{$_}++'
Reads stdin, and outputs each line only once - without sorting ahead of time. This does use more memory than your system's sort utility.

3
By: doherty
2011-02-17 02:18:44

4 Alternatives + Submit Alt

What Others Think

Sure, but it has to be understood that this approach uses a lot of memory.
depesz · 382 weeks and 5 days ago
+1 though, another pipe line is another fork which duplicates the entire process memory.
RanyAlbeg · 382 weeks and 5 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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