Test if the specified variable has a [n]on-empty value

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  • Check file types and compare values.
    Returns 0 if the condition evaluates to true, 1 if it evaluates to false.
    More information: <https://www.gnu.org/software/bash/manual/bash.html#index-test>.
  • Trick copyright: tl;dr; <https://github.com/tldr-pages/tldr>

[ -n "${{variable}}" ]

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