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{

Multipurpose shell syntax. More information: https://www.gnu.org/software/bash/manual/bash.html.

  • Isolate variable names:

echo ${{{HOME}work}}

  • Brace expand sequences:

echo {{{1..3}}} {{{a..c}}}{{{dir1,dir2,dir3}}}

  • Check if variable is set before returning text:

echo ${{{variable:+variable is set and contains $variable}}}

  • Set default values in case variable is unset:

echo ${{{variable:-default}}}

  • Return variable length in characters:

echo ${{{#variable}}}

  • Return a string slice:

echo ${{{variable:3:7}}}

  • Recursively expand a variable:

echo ${{{!variable}}}

  • Group command output together:

{ {{command1; command2; ...}} } | {{another_command}}