CharLikeChunks

The context used to pull chunks and iterate over characters. Implementations might decide to have immutable or mutable contexts depending on performance constraints that are desired.

Advances one character in the context. This method is called for stepping through characters, so it is preferrable to have it efficient. Implemetations can be based on mutable Context, as a new one is created locally by the parsers.

This should not perform any effect or pull.

Implementations can assume that needsPull will be called after this step function to check boundaries within the current chunk in the context.

Creates a context out of a stream.

Returns the current character in the context.

Implementations can assume this will never fail, as parsers will check for needsPull and pullNext before calling this function.

This should not perform any effect or pull and must be pure.

Decides whether a new chunk must be pulled from the context.

Pulls the next chunk from the context. Returns None if stream is exhausted.