Generate a cache that targets a specific encoding for calculating code unit offsets.
Returns a cache that is the identity function in order to maintain the same interface. We can do this because code units are always equivalent to byte offsets for ASCII-only sources.
The character offset from the beginning of the source where this location starts.
The character offset from the beginning of the source where this location ends.
The column number in characters where this location ends from the start of the line.
The column number in characters where this location ends from the start of the line.
Create a code units cache for the given encoding.
Visits the child nodes of ‘node` by calling `accept` on each one.
Read a single encoding valid character from the input.