This function when supplied a block, do executes as if BLOCK were a function, returning the value of the last statement evaluated in the block.
When supplied with EXPR, do executes the file specified by EXPR as if it were another Perl script.
If supplied a subroutine, SUB, do executes the subroutine using LIST as the arguments, raising an exception if SUB hasn.t been defined.
Following is the simple syntax for this function −
do BLOCK do EXPR do SUB(LIST)
This function returns the value of the last statement evaluated in the block.