exrex:tldr:6bbc4

The command you have provided is written in a syntax of a command line tool called exrex. exrex is a tool used for generating strings that match a given regular expression.

Let's break down the command and understand each part:

1. exrex: It is the name of the command line tool itself. By running this command, you are invoking the exrex tool.

2. ${( )}: This is a syntax used by Zsh, a shell program. It allows the evaluation of expressions inside curly brackets.

3. {20}(\| *\\|-{22}|\|): This is a regular expression pattern enclosed within parentheses.

   • {20} matches exactly 20 characters.
   • (\| *\\|-{22}|\|) is an alternation group, meaning it matches any one of the three options inside parentheses:
     • \| *\\: Matches a vertical bar | followed by zero or more spaces and a backslash \.
     • -{22}: Matches a dash - repeated exactly 22 times.
     • \|: Matches a vertical bar |.

4. \-={50}: Matches a dash - followed by exactly 50 equal signs =.

5. ( ){0,5}\\\-: Matches a group of spaces, repeated between 0 to 5 times, followed by a backslash \ and a dash -.

6. {12}~{39}: Matches exactly 12 spaces, followed by a tilde ~, and then followed by exactly 39 spaces.

Overall, this command is generating random strings that match the provided regular expression pattern. The resulting strings will have various combinations of vertical bars, spaces, dashes, equal signs, and tildes according to the given pattern.