DIRECTORY Rope, RuntimeError, TextNode, TiogaRopes;TiogaRopesImpl: CEDAR PROGRAMIMPORTS Rope, RuntimeError, TextNodeEXPORTS TiogaRopes=BEGIN OPEN TiogaRopes;Location: TYPE = TextNode.Location;TiogaRope: TYPE = REF TiogaRopePrivate;TiogaRopePrivate: TYPE = RECORD [node: Node,start, length: INT,skipCommentNode: BOOL,curNode: Node _ NIL,curNodeStart, curNodeLength: INT _ 0,curRope: ROPE];RopeFromTioga: PUBLIC PROC [node: Node, start: INT _ 0, length: INT _ LAST[INT], skipCommentNode: BOOL _ FALSE] RETURNS [asRope: ROPE] = {end: Location = DocEnd[node, skipCommentNode];nodeLoc: Location = [node, 0];remSize: INT = TextNode.LocOffset[nodeLoc, end, 1, skipCommentNode];IF start >= remSize THEN RETURN [NIL];{curRope: ROPE = node.NodeRope[];tr: TiogaRope = NEW [TiogaRopePrivate _ [node: node,start: start,length: MIN[length, remSize - start],skipCommentNode: skipCommentNode,curNode: node,curNodeStart: 0,curNodeLength: curRope.Length[],curRope: curRope]];asRope _ Rope.MakeRope[tr, tr.length, FetchFromTiogaRope];}};JumpTo: PROC [tr: TiogaRope, index: INT] = {newOffset: INT = tr.start+index;here: Location = IF newOffset >= tr.curNodeStart/2 THEN LocRelative[[tr.curNode, 0], newOffset-tr.curNodeStart, 1, tr.skipCommentNode] ELSE LocRelative[[tr.node, 0], newOffset, 1, tr.skipCommentNode];tr.curNode _ here.node;tr.curNodeStart _ newOffset - here.where;tr.curRope _ TextNode.NodeRope[tr.curNode];tr.curNodeLength _ tr.curRope.Length[];};LocRelative: PROC [location: Location, count: INT, break: NAT _ 1, skipCommentNodes: BOOL _ FALSE] RETURNS [rel: Location] = {SELECT count FROM=0 => rel _ location --avoid the bogosity in TextNodeImpl.LocRelative--;>0 => rel _ TextNode.LocRelative[location, count, break, skipCommentNodes];<0 => {--TextNodeImpl.LocRelative won't backup over node boundariesbackParent: Node _ NIL;rel _ location;WHILE count + rel.where < 0 DOcount _ count + rel.where;[rel.node, backParent, ] _ TextNode.Backward[rel.node, backParent];rel.where _ IF (NOT skipCommentNodes) OR (NOT rel.node.comment) THEN rel.node.rope.Length[] + break ELSE 0;ENDLOOP;rel.where _ count + rel.where;};ENDCASE => ERROR;rel _ rel;};FetchFromTiogaRope: PROC [data: REF, index: INT] RETURNS [char: CHAR] --Rope.FetchType-- = {tr: TiogaRope = NARROW[data];IF NOT index IN [0 .. tr.length) THEN ERROR RuntimeError.BoundsFault;IF NOT index+tr.start - tr.curNodeStart IN [0 .. tr.curNodeLength] THEN JumpTo[tr, index];index _ index+tr.start - tr.curNodeStart;char _ IF index < tr.curNodeLength THEN tr.curRope.Fetch[index] ELSE '\n;};DocEnd: PROC [node: Node, skipCommentNode: BOOL] RETURNS [endLoc: Location] = {endNode: Node _ TextNode.Root[node];IF endNode = NIL THEN ERROR;DOnext: Node _ TextNode.LastChild[endNode];IF next = NIL THEN EXIT;endNode _ next;ENDLOOP;IF skipCommentNode THEN WHILE endNode.comment DO endNode _ TextNode.StepBackward[endNode] ENDLOOP;endLoc _ [endNode, TextNode.NodeRope[endNode].Length[]+1];};END.   H  TiogaRopesImpl.mesaMike Spreitzer August 5, 1986 4:26:06 pm PDT ‌ت‹  –"cedar" styleک code™K™,—Kک Kڑدk	œ*ک3Kک ڑدnœ‌œ‌کKڑ‌œک$Kڑ‌œکKک—Kک Kڑ‌œ‌œکKک Kڑœ
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