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//
// ParseTree.m
// ANTLR
//
// Created by Alan Condit on 7/12/10.
// [The "BSD licence"]
// Copyright (c) 2010 Alan Condit
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
// 1. Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// 2. Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
// 3. The name of the author may not be used to endorse or promote products
// derived from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
// IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
// OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
// IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
// NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
// THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#import "ParseTree.h"
/** A record of the rules used to match a token sequence. The tokens
* end up as the leaves of this tree and rule nodes are the interior nodes.
* This really adds no functionality, it is just an alias for CommonTree
* that is more meaningful (specific) and holds a String to display for a node.
*/
@implementation ParseTree
+ (ParseTree *)newParseTree:(id<Token>)label
{
return [[ParseTree alloc] initWithLabel:label];
}
- (id)initWithLabel:(id<Token>)label
{
self = [super init];
if ( self != nil) {
payload = [label retain];
}
return self;
}
- (id<BaseTree>)dupNode
{
return nil;
}
- (NSInteger)type
{
return 0;
}
- (NSString *)text
{
return [self toString];
}
- (NSInteger)getTokenStartIndex
{
return 0;
}
- (void)setTokenStartIndex:(NSInteger)anIndex
{
}
- (NSInteger)getTokenStopIndex
{
return 0;
}
- (void)setTokenStopIndex:(NSInteger)anIndex
{
}
- (NSString *)description
{
if ( [payload isKindOfClass:[CommonToken class]] ) {
id<Token> t = (id<Token>)payload;
if ( t.type == TokenTypeEOF ) {
return @"<EOF>";
}
return [t text];
}
return [payload description];
}
- (NSString *)toString
{
return [self description];
}
/** Emit a token and all hidden nodes before. EOF node holds all
* hidden tokens after last real token.
*/
- (NSString *)toStringWithHiddenTokens
{
NSMutableString *buf = [NSMutableString stringWithCapacity:25];
if ( hiddenTokens!=nil ) {
for (NSUInteger i = 0; i < [hiddenTokens count]; i++) {
id<Token> hidden = (id<Token> ) [hiddenTokens objectAtIndex:i];
[buf appendString:[hidden text]];
}
}
NSString *nodeText = [self toString];
if ( ![nodeText isEqualTo:@"<EOF>"] )
[buf appendString:nodeText];
return buf;
}
/** Print out the leaves of this tree, which means printing original
* input back out.
*/
- (NSString *)toInputString
{
NSMutableString *buf = [NSMutableString stringWithCapacity:25];
[self _toStringLeaves:buf];
return buf;
}
- (void)_toStringLeaves:(NSMutableString *)buf
{
if ( [payload isKindOfClass:[CommonToken class]] ) { // leaf node token?
[buf appendString:[self toStringWithHiddenTokens]];
return;
}
for (int i = 0; children!=nil && i < [children count]; i++) {
ParseTree *t = (ParseTree *) [children objectAtIndex:i];
[t _toStringLeaves:buf];
}
}
@synthesize payload;
@synthesize hiddenTokens;
//@synthesize children;
//@synthesize anException;
@end