Key
Key[key]
represents a key used to access a value in an association.
Key[key][assoc]
extracts the value corresponding to key in the association assoc.
Details

- Key is used in functions such as Part to access values in Association objects.
- Key can normally be omitted when key is a string.
Examples
Basic Examples (4)
Extract a value from an association as a part:
Extract a value from an association by function application:
The Key wrapper is not necessary when the key is a string:
Lookups in associations interoperate with parts in lists and other expressions:
The explicit Key can be omitted when the keys in an association are strings:
Key is normally generated by functions such as Position:
Use Extract to extract the values:
Introduced in 2014
(10.0)