Apple II Memory Map

This is the rust binding to a database of Apple II special addresses intended to be used with language servers. The central element is the file map.json which maps addresses to a set of descriptive strings.

Map Records

The map records correspond to the structure

pub struct AddressInfo {
    pub brief: Option<String>,
    pub ctx: Option<String>,
    pub desc: String,
    pub label: Option<String>,
    pub note: Option<String>,
    pub subctx: Option<String>,
    pub typ: String
}

Information is accessed through the opaque struct MemoryMap. The whole database can be borrowed as a HashMap as follows:

let a2map = MemoryMap::new();
let full_map: &HashMap<u16,AddressInfo> = a2map.get_all();

To get a single record use

let maybe_info: Option<AddressInfo> = a2map.get_one(addr);

The argument addr can range from -32767 to 65535. As an example get_one(0xfded) will give the rust equivalent of

{
  brief: 'Print character in A',
  desc: 'Invoke output routine whose address is in (56).  Usually prints character in A.',
  label: 'COUT',
  type: 'ROM routine'
}

AddressInfo Fields

• brief: short description suitable for display in a selection box
• ctx: notes on limiting context, such as hardware requirements, applicability to given language, etc.
• desc: long description suitable for hovers
• label: suggested assembler label
• note: any other notes
• subctx: notes on sub context, e.g., specific aspect of a language
• type: data type (e.g. word) or operation type (e.g. ROM routine, soft switch)

Multi-context Records

The map.json file uses logic expressions to delineate information by context, e.g., ctx might have the value "Applesoft | Integer BASIC". The rust binding provides a function to parse the logic and produce an array of records, with each element corresponding to a given context:

let maybe_records: Option<Vec<AddressInfo>> = a2map.get_one_and_split(addr);

If there is no splitting of the ctx field, no other fields will be split. It is not required to use this function. If get_one is used instead, downstream will receive the logic expressions, which can be parsed in any manner desired.