[Pixel]<Tioga>TBase>editAddrs.mesa!1

-- EditAddrs.Mesa

-- written by Paxton. March 1981

-- last written by Paxton. August 11, 1982 10:32 am

-- **** Persistent addressing ****

DIRECTORY

TextNode;

EditAddrs: DEFINITIONS =

BEGIN

Ref: TYPE = REF Body;

Body: TYPE = RECORD [addrs: Pair];

RefTextNode: TYPE = TextNode.RefTextNode;

Offset: TYPE = TextNode.Offset;

Pair: TYPE = REF PairBody;

PairBody: TYPE = RECORD [next: Pair, addr: REF, location: Offset];

Create: PROC RETURNS [Ref];

PutAddr: PROC [ref: Ref, addr: REF, location: Offset];

-- assigns addr to location in ref

-- ok if addr was previously assigned elsewhere

RemAddr: PROC [ref: Ref, addr: REF];

-- removes the given addr

GetAddr: PROC [ref: Ref, addr: REF] RETURNS [location: Offset];

-- generates OffsetAddrs.AddrNotFound if the addr is not in the mapping

AddrNotFound: ERROR;

TryGetAddr: PROC [ref: Ref, addr: REF]

RETURNS [found: BOOLEAN, location: Offset];

MapAddrs: PROC [ref: Ref, action: MapAddrsAction]

RETURNS [BOOLEAN];

-- apply the action to each addr&location pair for the ref

-- returns true if&when an action returns true

MapAddrsAction: TYPE = PROC [addr: REF, location: Offset] RETURNS [BOOLEAN];

-- **** notify proc registration ****

AddNotifyProc, RemoveNotifyProc: PROC [proc: AddrNotifyProc];

AddrNotifyProc: TYPE = PROC [node: RefTextNode, new: PROC [old: Offset] RETURNS [Offset]];

-- **** Editing Operations for persistent addrs ****

Replace: PROC [node: RefTextNode, start, len, newlen: Offset];

-- replace chars in [start..start+len) by newlen chars

-- addrs that are in the replaced section move to start

-- add (newlen-len) to addrs that are after the replaced section

-- **** Update Functions for persistent addrs ****

AfterReplace: PROC [initLoc, start, len, newlen: Offset] RETURNS [newLoc: Offset];

Start: PROC; -- for initialization only

END.