Linked List in Perl 6
Implement a doubly linked list
exercism fetch perl6 linked-list
Implement a doubly linked list.
Like an array, a linked list is a simple linear data structure. Several common data types can be implemented using linked lists, like queues, stacks, and associative arrays.
A linked list is a collection of data elements called nodes. In a singly linked list each node holds a value and a link to the next node. In a doubly linked list each node also holds a link to the previous node.
You will write an implementation of a doubly linked list. Implement a Node to hold a value and pointers to the next and previous nodes. Then implement a List which holds references to the first and last node and offers an array-like interface for adding and removing items:
push(insert value at back);
pop(remove value at back);
shift(remove value at front).
unshift(insert value at front);
To keep your implementation simple, the tests will not cover error
shift will never be called on an
If you want to know more about linked lists, check Wikipedia.
Running the tests
There is a test suite and module included with the exercise.
The test suite (a file with the extension
.t) will attempt to run routines
from the module (a file with the extension
Add/modify routines in the module so that the tests will pass! You can view the
test data by executing the command
perl6 --doc *.t (* being the name of the
test suite), and run the test suite for the exercise by executing the command
prove . --exec=perl6 in the exercise directory.
You can also add the
-v flag e.g.
prove . --exec=perl6 -v to display all
tests, including any optional tests marked as 'TODO'.
Classic computer science topic