Design Proposal: Parser Context Struct

[mjbozo]

A problem faced when performing the parsing step is keeping track of the context the current component is being parsed in.

Currently the parser has access to previous, current, and next tokens, which is not always enough to understand the whole context.

Having some sort of context struct which can keep track of multiple aspects of the program could make a range of scenarios easier to handle and result in nicer code.

One idea could be to include a stack consisting of all the parent components, so we know the surrounding components.

This idea needs a bit more thought and analysis on whether this is the right approach.