test for membership
Description
x member(X, x)
If X is a set, member(X, x) succeeds if x is a member of X but fails otherwise. If X is a table, member(X, x) succeeds if x is a key of an element in X but fails otherwise. member(X, x) produces x if it succeeds.
Parameters
- X
- set or table
- x
- possible key in X
- returns
- x or fail
Errors
122 |
X is not a set or table |
See Also