Abstract type: Difference between revisions
Content added Content deleted
| Line 111: | Line 111: | ||
There is no constructor for the class. However to prevent the class ever being associated with an instance it suffices to force the validator to fail. |
There is no constructor for the class. However to prevent the class ever being associated with an instance it suffices to force the validator to fail. |
||
<lang python>class Stack() |
<lang python>class Stack() |
||
def !valid?(object) nil |
def !valid?(object) nil |
||
tag Stack some-object ; always fails</lang> |
|||
=={{header|Haskell}}== |
=={{header|Haskell}}== |
||