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   Ben Zanin (gnomon@mastodon.social)'s status on Friday, 14-Feb-2025 12:28:31 JST Ben Zanin

   in reply to

   • Julia Evans

   @b0rk the reason I use this is that my ~/.profile and ~/.bashrc files mix direct assignment to $PATH with appending/prepending values, in some cases because that's how external tools I call have set themselves up. This deduplication hack lets me insert synchronization points that ensure re-source'ing my ~/.bashrc is idempotent, instead of accumulating a longer and longer value which I usually fail to notice.

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   • Haelwenn /элвэн/ :triskell: likes this.
   • Embed this notice
     Ben Zanin (gnomon@mastodon.social)'s status on Friday, 14-Feb-2025 12:28:32 JST Ben Zanin

     in reply to

     • Julia Evans

     @b0rk so first the trick, then the reasons for it:

     mapfile -t paths < <(<<< "$PATH" tr ':' $'\n' | awk '!seen[$0]++'); printf -v 'PATH' ':%s' "${paths[@]}"; PATH=${PATH:1}

     The real trick is that the awk step deduplicates entries _without changing the order of the path elements_, which of course is crucial in this case. The printf/PATH=... step is just about reassembling the array of results back into a string with minimal opportunities for errors to creep in.

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   • Embed this notice
     Ben Zanin (gnomon@mastodon.social)'s status on Friday, 14-Feb-2025 12:28:33 JST Ben Zanin

     in reply to

     • Julia Evans

     @b0rk do you mind if I share my favourite $PATH deduplication trick?

   • Embed this notice
     Julia Evans (b0rk@social.jvns.ca)'s status on Friday, 14-Feb-2025 12:28:33 JST Julia Evans

     in reply to

     @gnomon yeah i'd be interested, i've never known how to do that really

     i'd also be curious about how you use it

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     Julia Evans (b0rk@social.jvns.ca)'s status on Friday, 14-Feb-2025 12:28:34 JST Julia Evans

     how to add a directory to your PATH https://jvns.ca/blog/2025/02/13/how-to-add-a-directory-to-your-path/