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   Will Thompson (wjt@mastodon.me.uk)'s status on Tuesday, 07-Nov-2023 07:48:27 JST Will Thompson

   In the last year or so I read an article thoroughly investigating whether the idiom

   [ x$foo = x ]

   is still needed in modern-day /bin/sh, concluding that it is not if you quote the variable. But it's surprisingly hard to search for. Does anyone happen to have a link lying around?

   Edit: found it! https://www.vidarholen.net/contents/blog/?p=1035

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     Haelwenn /элвэн/ :triskell: (lanodan@queer.hacktivis.me)'s status on Tuesday, 07-Nov-2023 08:09:46 JST Haelwenn /элвэн/ :triskell:

     in reply to

     • eukara :steampowered:

     @eukara @wjt I've seen it many times, specially in ./configure scripts (auto*hell or not), in fact I wouldn't be surprised to have written similar ones myself either due to:
     - Cargo-cult / keeping things consistent with the rest of the code;
     - Rules around shell quoting being a PITA;
     - Not wanting pure-whitespace/empty-string to be truthful. Like ${foo:-yes} and ${foo:=yes} only acts if it's actually undefined. And how test -n $foo is for empty string;
     - Outside of nicely defined commands like test: GNU and it's annoying implementation of getopt.

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     eukara :steampowered: (eukara@idtech.space)'s status on Tuesday, 07-Nov-2023 08:09:47 JST eukara :steampowered:

     in reply to
     @wjt That was a fun read, love me some UNIX history. Don't think I've come across this hack myself before