[Indigo]<Cedar>Tioga>TreeFind.mesa!1

-- TreeFind.mesa

-- written by Bill Paxton, June 1981

-- last edit by Bill Paxton, December 30, 1982 10:30 am

-- This module provides a "Find" operation for text in trees

-- The pattern matching is done by TextFind.Mesa

-- This module simply walks the tree (forward or backwards) applying the text

DIRECTORY

TextFind,

TextNode,

NameSymbolTable,

Rope;

TreeFind: CEDAR DEFINITIONS IMPORTS TextFind =

BEGIN

Ref: TYPE = TextNode.Ref;

RefTextNode: TYPE = TextNode.RefTextNode;

Offset: TYPE = TextNode.Offset;

ROPE: TYPE = Rope.ROPE;

MaxLen: Offset = LAST[Offset];

Finder: TYPE = TextFind.Finder;

Create: PROC [

pattern: RefTextNode, literal, word, ignoreLooks, ignoreCase, addBounds: BOOLEAN ← FALSE,

patternStart: Offset ← 0, patternLen: Offset ← MaxLen]

RETURNS [Finder] = INLINE { RETURN [TextFind.Create[

pattern,literal,word,ignoreLooks,ignoreCase,addBounds,patternStart,patternLen]] };

-- creates a record containing a "compiled" version of the pattern

-- see TextFind.Mesa for more info about patterns

-- if literal is true, each character in pattern is taken literally

-- if word flag is true, pattern only matches if no adjacent letters or digits

-- if ignoreLooks if true, then ignore the looks of the pattern characters

-- if ignoreCase is false, then alpha chars in pattern must match case

-- otherwise, they can match either upper or lower

-- if addBounds is true, add |'s to both ends of pattern

CreateFromRope: PROC [pattern: ROPE, literal, word, ignoreCase, addBounds: BOOLEAN ← FALSE,

patternStart: Offset ← 0, patternLen: Offset ← MaxLen]

RETURNS [Finder] = INLINE { RETURN [TextFind.CreateFromRope[

pattern,literal,word,ignoreCase,addBounds,patternStart,patternLen]] };

CommentControl: TYPE = { includeComments, excludeComments, commentsOnly };

Try: PROC [finder: Finder, first: Ref, start: Offset ← 0,

last: Ref ← NIL, lastLen: Offset ← MaxLen, looksExact: BOOLEAN ← FALSE,

commentControl: CommentControl ← includeComments,

checkType: BOOLEAN ← FALSE, type: TextNode.TypeName ← TextNode.nullTypeName,

checkStyle: BOOLEAN ← FALSE, style: NameSymbolTable.Name ← NameSymbolTable.nullName,

styleProc: PROC [Ref] RETURNS [NameSymbolTable.Name] ← NIL,

interrupt: REF BOOL ← NIL]

RETURNS [found: BOOLEAN, where: RefTextNode, at, atEnd, before, after: Offset];

-- searches first node beginning at start

-- continues until finds a match or reaches last node

-- seaches lastLen chars in last node; seaches to end of other nodes

-- if finds a match, returns with found = true,

-- at = beginning of match or location corresponding to { in pattern

-- atEnd = end of match or location corresponding to } in pattern

-- after = end of entire match, which may be > atEnd if used } in pattern

-- before = start of entire match, which may be < at if used { in pattern

-- if looksExact is true, then match by equality, else by subset

-- commentControl allows restriction of search to comments/noncomments

-- if checkType is true, then only match in nodes with given type

-- if checkStyle is true, then only match in nodes with given style

-- styleProc is supplied so called can determine style for nodes

-- if just interested in type/style, can pass finder=NIL

-- if interrupt^ becomes true, will stop searching

TryBackwards: PROC [finder: Finder, first: Ref,

len: Offset ← MaxLen, last: Ref ← NIL, lastStart: Offset ← 0,

looksExact: BOOLEAN ← FALSE, commentControl: CommentControl ← includeComments,

checkType: BOOLEAN ← FALSE, type: TextNode.TypeName ← TextNode.nullTypeName,

checkStyle: BOOLEAN ← FALSE, style: NameSymbolTable.Name ← NameSymbolTable.nullName,

styleProc: PROC [Ref] RETURNS [NameSymbolTable.Name] ← NIL,

interrupt: REF BOOL ← NIL]

RETURNS [found: BOOLEAN, where: RefTextNode, at, atEnd, before, after: Offset];

-- searches first node from start=0 to end=len

-- continues back through tree until finds a match or reaches last node

-- searches from lastStart in last node; searches from 0 in other nodes

Apply: PROC [finder: Finder, first: Ref, proc: ApplyProc, start: Offset ← 0,

last: Ref ← NIL, lastLen: Offset ← MaxLen, looksExact: BOOLEAN ← FALSE,

commentControl: CommentControl ← includeComments,

checkType: BOOLEAN ← FALSE, type: TextNode.TypeName ← TextNode.nullTypeName,

checkStyle: BOOLEAN ← FALSE, style: NameSymbolTable.Name ← NameSymbolTable.nullName,

styleProc: PROC [Ref] RETURNS [NameSymbolTable.Name] ← NIL]

RETURNS [count: LONG INTEGER];

-- finds a span of text and calls proc

ApplyProc: TYPE = PROC [where: RefTextNode, at, atEnd, before, after: Offset]

RETURNS [continue, bumpCount: BOOLEAN, from, delta: Offset];

-- arg's are results from Try

-- if continue is true, Apply will Try again starting at "from" in "where"

-- delta tells change in length caused by the action

-- Apply does the following with delta

-- IF where=last AND lastLen < MaxLen THEN lastLen ← lastLen+delta

-- if bumpCount is true, Apply will increment its result counter

END.