typeset:tldr:32abf

The command "typeset ${variable}=(${item_a item_b item_c})" is used to declare and initialize an array variable in the Bash shell.

Here's a breakdown of the command:

• "typeset" is a command used to define variable attributes or set options in Bash. In this case, it is used to declare the variable.
• "${variable}" is the name of the variable being declared. The actual name of the variable is stored in the variable "variable" and the "${}" syntax is used to access its value.
• "=" is the assignment operator, used to assign a value to the variable being declared.
• "(${item_a item_b item_c})" is an array being assigned to the variable. The values "item_a", "item_b", and "item_c" are enclosed in parentheses () and separated by spaces, indicating they are elements of the array.

After executing this command, the variable named by the value of "variable" will be declared as an array and will contain the elements "item_a", "item_b", and "item_c".