This saves 2 strokes over yours: 

perl -plE"@h{/./g}++;$_=keys%h"

[download]

And this saves 2 more over your version of tye's: 

perl -lpE'$_=s/(.)(?!.*\1)//g'

[download]
With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^2: Golf for unique digits by BrowserUk
in thread Golf for unique digits by Cody Fendant

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