|StringVariable||String value to chop. Can be either a value or @VarName (will upvar and read/write).|
|Count||Optional. How many characters to chop. Default is 1.|
string rangeand has behavior consistent with values that are less than zero or past the end of the string.
Note that arguments of the form XxxVariable can take either a normal value or the name of a variable to read/write, prefixed by @. See About Using @ for details.