KeyMapping typedef

String KeyMapping (
  1. String str
)

Often it is desirable to define equivalences between Key strings, for example for case insensitivity.

This is achieved via the surjection:

  • m : SK ⊆ S

such that:

  • S is set of all strings
  • K is set of Keys

m(m(x)) = m(x), i.e. m must be idempotent, repeated applications do not change the result.

For example:

  • m(x) = lowercase(x).

KeyMapping is optionally specified during construction and applied to keys during all operations.

If no KeyMapping is supplied then the default identity function is used.

  • m(x) = x.

Predefined mappings include:

If str is null then the name of the keymapping is returned.

Implementation

typedef KeyMapping = String Function(String str);