Using the let builtin, a string can easily be created by specifying the name, and an expression that will be evaluated before assigning it to that variable.

let git_branch = $(git rev-parse --abbrev-ref HEAD ^> /dev/null)

To call a string variable, you may utilize the $ sigil along with the name of the variable. For more information on expansions, see the expansions section of this manual.

echo $git_branch

Strings can be sliced in Ion using a range.

let foo = "Hello, World"
echo $foo[..5]
echo $foo[7..]
echo $foo[2..9]

The drop command may be used to drop string variables.

let variable = "testing"
echo $variable
drop variable
echo $variable