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Scanner style.

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Ferdinand Majerech 2014-07-26 23:29:55 +02:00
parent f76e4cfd02
commit d5663b1e57
1 changed files with 172 additions and 197 deletions
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363
source/dyaml/scanner.d
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@ -4,10 +4,8 @@
// (See accompanying file LICENSE_1_0.txt or copy at // (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt) // http://www.boost.org/LICENSE_1_0.txt)
/** /// YAML scanner.
* YAML scanner. /// Code based on PyYAML: http://www.pyyaml.org
* Code based on PyYAML: http://www.pyyaml.org
*/
module dyaml.scanner; module dyaml.scanner;
@ -34,36 +32,32 @@ import dyaml.style;
import dyaml.token; import dyaml.token;
package: package:
/** /// Scanner produces tokens of the following types:
* Scanner produces tokens of the following types: /// STREAM-START
* STREAM-START /// STREAM-END
* STREAM-END /// DIRECTIVE(name, value)
* DIRECTIVE(name, value) /// DOCUMENT-START
* DOCUMENT-START /// DOCUMENT-END
* DOCUMENT-END /// BLOCK-SEQUENCE-START
* BLOCK-SEQUENCE-START /// BLOCK-MAPPING-START
* BLOCK-MAPPING-START /// BLOCK-END
* BLOCK-END /// FLOW-SEQUENCE-START
* FLOW-SEQUENCE-START /// FLOW-MAPPING-START
* FLOW-MAPPING-START /// FLOW-SEQUENCE-END
* FLOW-SEQUENCE-END /// FLOW-MAPPING-END
* FLOW-MAPPING-END /// BLOCK-ENTRY
* BLOCK-ENTRY /// FLOW-ENTRY
* FLOW-ENTRY /// KEY
* KEY /// VALUE
* VALUE /// ALIAS(value)
* ALIAS(value) /// ANCHOR(value)
* ANCHOR(value) /// TAG(value)
* TAG(value) /// SCALAR(value, plain, style)
* SCALAR(value, plain, style)
*/
/** /// Marked exception thrown at scanner errors.
* Marked exception thrown at scanner errors. ///
* /// See_Also: MarkedYAMLException
* See_Also: MarkedYAMLException
*/
class ScannerException : MarkedYAMLException class ScannerException : MarkedYAMLException
{ {
mixin MarkedExceptionCtors; mixin MarkedExceptionCtors;
@ -182,53 +176,46 @@ final class Scanner
reader_ = null; reader_ = null;
} }
/** /// Check if the next token is one of specified types.
* Check if the next token is one of specified types. ///
* /// If no types are specified, checks if any tokens are left.
* If no types are specified, checks if any tokens are left. ///
* /// Params: ids = Token IDs to check for.
* Params: ids = Token IDs to check for. ///
* /// Returns: true if the next token is one of specified types, or if there are
* Returns: true if the next token is one of specified types, /// any tokens left if no types specified, false otherwise.
* or if there are any tokens left if no types specified.
* false otherwise.
*/
bool checkToken(const TokenID[] ids ...) @safe bool checkToken(const TokenID[] ids ...) @safe
{ {
//Check if the next token is one of specified types. //Check if the next token is one of specified types.
while(needMoreTokens()){fetchToken();} while(needMoreTokens()) { fetchToken(); }
if(!tokens_.empty) if(!tokens_.empty)
{ {
if(ids.length == 0){return true;} if(ids.length == 0) { return true; }
else else
{ {
const nextId = tokens_.peek().id; const nextId = tokens_.peek().id;
foreach(id; ids) foreach(id; ids)
{ {
if(nextId == id){return true;} if(nextId == id) { return true; }
} }
} }
} }
return false; return false;
} }
/** /// Return the next token, but keep it in the queue.
* Return the next token, but keep it in the queue. ///
* /// Must not be called if there are no tokens left.
* Must not be called if there are no tokens left.
*/
ref const(Token) peekToken() @safe ref const(Token) peekToken() @safe
{ {
while(needMoreTokens){fetchToken();} while(needMoreTokens) { fetchToken(); }
if(!tokens_.empty){return tokens_.peek();} if(!tokens_.empty) { return tokens_.peek(); }
assert(false, "No token left to peek"); assert(false, "No token left to peek");
} }
/** /// Return the next token, removing it from the queue.
* Return the next token, removing it from the queue. ///
* /// Must not be called if there are no tokens left.
* Must not be called if there are no tokens left.
*/
Token getToken() @safe Token getToken() @safe
{ {
while(needMoreTokens){fetchToken();} while(needMoreTokens){fetchToken();}
@ -276,92 +263,90 @@ final class Scanner
errorData_ = MarkedYAMLExceptionData(context, contextMark, problem, problemMark); errorData_ = MarkedYAMLExceptionData(context, contextMark, problem, problemMark);
} }
///Determine whether or not we need to fetch more tokens before peeking/getting a token. /// Determine whether or not we need to fetch more tokens before peeking/getting a token.
bool needMoreTokens() @safe pure bool needMoreTokens() @safe pure
{ {
if(done_) {return false;} if(done_) { return false; }
if(tokens_.empty){return true;} if(tokens_.empty) { return true; }
///The current token may be a potential simple key, so we need to look further. /// The current token may be a potential simple key, so we need to look further.
stalePossibleSimpleKeys(); stalePossibleSimpleKeys();
return nextPossibleSimpleKey() == tokensTaken_; return nextPossibleSimpleKey() == tokensTaken_;
} }
///Fetch at token, adding it to tokens_. /// Fetch at token, adding it to tokens_.
void fetchToken() @safe void fetchToken() @safe
{ {
///Eat whitespaces and comments until we reach the next token. // Eat whitespaces and comments until we reach the next token.
scanToNextToken(); scanToNextToken();
//Remove obsolete possible simple keys. // Remove obsolete possible simple keys.
stalePossibleSimpleKeys(); stalePossibleSimpleKeys();
//Compare current indentation and column. It may add some tokens // Compare current indentation and column. It may add some tokens
//and decrease the current indentation level. // and decrease the current indentation level.
unwindIndent(reader_.column); unwindIndent(reader_.column);
//Get the next character. // Get the next character.
const dchar c = reader_.peek(); const dchar c = reader_.peek();
//Fetch the token. // Fetch the token.
if(c == '\0') {return fetchStreamEnd();} if(c == '\0') { return fetchStreamEnd(); }
if(checkDirective()) {return fetchDirective();} if(checkDirective()) { return fetchDirective(); }
if(checkDocumentStart()) {return fetchDocumentStart();} if(checkDocumentStart()) { return fetchDocumentStart(); }
if(checkDocumentEnd()) {return fetchDocumentEnd();} if(checkDocumentEnd()) { return fetchDocumentEnd(); }
//Order of the following checks is NOT significant. // Order of the following checks is NOT significant.
if(c == '[') {return fetchFlowSequenceStart();} if(c == '[') { return fetchFlowSequenceStart(); }
if(c == '{') {return fetchFlowMappingStart();} if(c == '{') { return fetchFlowMappingStart(); }
if(c == ']') {return fetchFlowSequenceEnd();} if(c == ']') { return fetchFlowSequenceEnd(); }
if(c == '}') {return fetchFlowMappingEnd();} if(c == '}') { return fetchFlowMappingEnd(); }
if(c == ',') {return fetchFlowEntry();} if(c == ',') { return fetchFlowEntry(); }
if(checkBlockEntry()) {return fetchBlockEntry();} if(checkBlockEntry()) { return fetchBlockEntry(); }
if(checkKey()) {return fetchKey();} if(checkKey()) { return fetchKey(); }
if(checkValue()) {return fetchValue();} if(checkValue()) { return fetchValue(); }
if(c == '*') {return fetchAlias();} if(c == '*') { return fetchAlias(); }
if(c == '&') {return fetchAnchor();} if(c == '&') { return fetchAnchor(); }
if(c == '!') {return fetchTag();} if(c == '!') { return fetchTag(); }
if(c == '|' && flowLevel_ == 0){return fetchLiteral();} if(c == '|' && flowLevel_ == 0) { return fetchLiteral(); }
if(c == '>' && flowLevel_ == 0){return fetchFolded();} if(c == '>' && flowLevel_ == 0) { return fetchFolded(); }
if(c == '\'') {return fetchSingle();} if(c == '\'') { return fetchSingle(); }
if(c == '\"') {return fetchDouble();} if(c == '\"') { return fetchDouble(); }
if(checkPlain()) {return fetchPlain();} if(checkPlain()) { return fetchPlain(); }
throw new Error(format("While scanning for the next token, found " throw new ScannerException("While scanning for the next token, found character "
"character \'%s\', index %s that cannot start any token" "\'%s\', index %s that cannot start any token"
, c, to!int(c)), reader_.mark); .format(c, to!int(c)), reader_.mark);
} }
///Return the token number of the nearest possible simple key. /// Return the token number of the nearest possible simple key.
uint nextPossibleSimpleKey() @safe pure nothrow @nogc uint nextPossibleSimpleKey() @safe pure nothrow @nogc
{ {
uint minTokenNumber = uint.max; uint minTokenNumber = uint.max;
foreach(k, ref simpleKey; possibleSimpleKeys_) foreach(k, ref simpleKey; possibleSimpleKeys_)
{ {
if(simpleKey.isNull){continue;} if(simpleKey.isNull) { continue; }
minTokenNumber = min(minTokenNumber, simpleKey.tokenIndex); minTokenNumber = min(minTokenNumber, simpleKey.tokenIndex);
} }
return minTokenNumber; return minTokenNumber;
} }
/** /// Remove entries that are no longer possible simple keys.
* Remove entries that are no longer possible simple keys. ///
* /// According to the YAML specification, simple keys
* According to the YAML specification, simple keys /// - should be limited to a single line,
* - should be limited to a single line, /// - should be no longer than 1024 characters.
* - should be no longer than 1024 characters. /// Disabling this will allow simple keys of any length and
* Disabling this will allow simple keys of any length and /// height (may cause problems if indentation is broken though).
* height (may cause problems if indentation is broken though).
*/
void stalePossibleSimpleKeys() @safe pure void stalePossibleSimpleKeys() @safe pure
{ {
foreach(level, ref key; possibleSimpleKeys_) foreach(level, ref key; possibleSimpleKeys_)
{ {
if(key.isNull){continue;} if(key.isNull) { continue; }
if(key.line != reader_.line || reader_.charIndex - key.charIndex > 1024) if(key.line != reader_.line || reader_.charIndex - key.charIndex > 1024)
{ {
enforce(!key.required, enforce(!key.required,
new Error("While scanning a simple key", new ScannerException("While scanning a simple key",
Mark(key.line, key.column), Mark(key.line, key.column),
"could not find expected ':'", reader_.mark)); "could not find expected ':'", reader_.mark));
key.isNull = true; key.isNull = true;
@ -369,31 +354,26 @@ final class Scanner
} }
} }
/** /// Check if the next token starts a possible simple key and if so, save its position.
* Check if the next token starts a possible simple key and if so, save its position. ///
* /// This function is called for ALIAS, ANCHOR, TAG, SCALAR(flow), '[', and '{'.
* This function is called for ALIAS, ANCHOR, TAG, SCALAR(flow), '[', and '{'.
*/
void savePossibleSimpleKey() @safe pure void savePossibleSimpleKey() @safe pure
{ {
//Check if a simple key is required at the current position. // Check if a simple key is required at the current position.
const required = (flowLevel_ == 0 && indent_ == reader_.column); const required = (flowLevel_ == 0 && indent_ == reader_.column);
assert(allowSimpleKey_ || !required, "A simple key is required only if it is " assert(allowSimpleKey_ || !required, "A simple key is required only if it is "
"the first token in the current line. Therefore it is always allowed."); "the first token in the current line. Therefore it is always allowed.");
if(!allowSimpleKey_){return;} if(!allowSimpleKey_) { return; }
//The next token might be a simple key, so save its number and position. // The next token might be a simple key, so save its number and position.
removePossibleSimpleKey(); removePossibleSimpleKey();
const tokenCount = tokensTaken_ + cast(uint)tokens_.length; const tokenCount = tokensTaken_ + cast(uint)tokens_.length;
const line = reader_.line; const line = reader_.line;
const column = reader_.column; const column = reader_.column;
const key = SimpleKey(cast(uint)reader_.charIndex, const key = SimpleKey(cast(uint)reader_.charIndex, tokenCount, line,
tokenCount, cast(ushort)min(column, ushort.max), required);
line,
column < ushort.max ? cast(ushort)column : ushort.max,
required);
if(possibleSimpleKeys_.length <= flowLevel_) if(possibleSimpleKeys_.length <= flowLevel_)
{ {
@ -405,10 +385,10 @@ final class Scanner
possibleSimpleKeys_[flowLevel_] = key; possibleSimpleKeys_[flowLevel_] = key;
} }
///Remove the saved possible key position at the current flow level. /// Remove the saved possible key position at the current flow level.
void removePossibleSimpleKey() @safe pure void removePossibleSimpleKey() @safe pure
{ {
if(possibleSimpleKeys_.length <= flowLevel_){return;} if(possibleSimpleKeys_.length <= flowLevel_) { return; }
if(!possibleSimpleKeys_[flowLevel_].isNull) if(!possibleSimpleKeys_[flowLevel_].isNull)
{ {
@ -420,21 +400,19 @@ final class Scanner
} }
} }
/** /// Decrease indentation, removing entries in indents_.
* Decrease indentation, removing entries in indents_. ///
* /// Params: column = Current column in the file/stream.
* Params: column = Current column in the file/stream.
*/
void unwindIndent(const int column) @trusted void unwindIndent(const int column) @trusted
{ {
if(flowLevel_ > 0) if(flowLevel_ > 0)
{ {
//In flow context, tokens should respect indentation. // In flow context, tokens should respect indentation.
//The condition should be `indent >= column` according to the spec. // The condition should be `indent >= column` according to the spec.
//But this condition will prohibit intuitively correct // But this condition will prohibit intuitively correct
//constructions such as // constructions such as
//key : { // key : {
//} // }
//In the flow context, indentation is ignored. We make the scanner less //In the flow context, indentation is ignored. We make the scanner less
//restrictive than what the specification requires. //restrictive than what the specification requires.
@ -446,7 +424,7 @@ final class Scanner
return; return;
} }
//In block context, we may need to issue the BLOCK-END tokens. // In block context, we may need to issue the BLOCK-END tokens.
while(indent_ > column) while(indent_ > column)
{ {
indent_ = indents_.back; indent_ = indents_.back;
@ -455,13 +433,11 @@ final class Scanner
} }
} }
/** /// Increase indentation if needed.
* Increase indentation if needed. ///
* /// Params: column = Current column in the file/stream.
* Params: column = Current column in the file/stream. ///
* /// Returns: true if the indentation was increased, false otherwise.
* Returns: true if the indentation was increased, false otherwise.
*/
bool addIndent(int column) @trusted bool addIndent(int column) @trusted
{ {
if(indent_ >= column){return false;} if(indent_ >= column){return false;}
@ -471,7 +447,7 @@ final class Scanner
} }
///Add STREAM-START token. /// Add STREAM-START token.
void fetchStreamStart() @safe nothrow void fetchStreamStart() @safe nothrow
{ {
tokens_.push(streamStartToken(reader_.mark, reader_.mark, reader_.encoding)); tokens_.push(streamStartToken(reader_.mark, reader_.mark, reader_.encoding));
@ -504,13 +480,13 @@ final class Scanner
tokens_.push(directive); tokens_.push(directive);
} }
///Add DOCUMENT-START or DOCUMENT-END token. /// Add DOCUMENT-START or DOCUMENT-END token.
void fetchDocumentIndicator(TokenID id)() @safe void fetchDocumentIndicator(TokenID id)() @safe
if(id == TokenID.DocumentStart || id == TokenID.DocumentEnd) if(id == TokenID.DocumentStart || id == TokenID.DocumentEnd)
{ {
//Set indentation to -1 . // Set indentation to -1 .
unwindIndent(-1); unwindIndent(-1);
//Reset simple keys. Note that there can't be a block collection after '---'. // Reset simple keys. Note that there can't be a block collection after '---'.
removePossibleSimpleKey(); removePossibleSimpleKey();
allowSimpleKey_ = false; allowSimpleKey_ = false;
@ -519,16 +495,16 @@ final class Scanner
tokens_.push(simpleToken!id(startMark, reader_.mark)); tokens_.push(simpleToken!id(startMark, reader_.mark));
} }
///Aliases to add DOCUMENT-START or DOCUMENT-END token. /// Aliases to add DOCUMENT-START or DOCUMENT-END token.
alias fetchDocumentIndicator!(TokenID.DocumentStart) fetchDocumentStart; alias fetchDocumentIndicator!(TokenID.DocumentStart) fetchDocumentStart;
alias fetchDocumentIndicator!(TokenID.DocumentEnd) fetchDocumentEnd; alias fetchDocumentIndicator!(TokenID.DocumentEnd) fetchDocumentEnd;
///Add FLOW-SEQUENCE-START or FLOW-MAPPING-START token. /// Add FLOW-SEQUENCE-START or FLOW-MAPPING-START token.
void fetchFlowCollectionStart(TokenID id)() @trusted void fetchFlowCollectionStart(TokenID id)() @trusted
{ {
//'[' and '{' may start a simple key. // '[' and '{' may start a simple key.
savePossibleSimpleKey(); savePossibleSimpleKey();
//Simple keys are allowed after '[' and '{'. // Simple keys are allowed after '[' and '{'.
allowSimpleKey_ = true; allowSimpleKey_ = true;
++flowLevel_; ++flowLevel_;
@ -537,16 +513,16 @@ final class Scanner
tokens_.push(simpleToken!id(startMark, reader_.mark)); tokens_.push(simpleToken!id(startMark, reader_.mark));
} }
///Aliases to add FLOW-SEQUENCE-START or FLOW-MAPPING-START token. /// Aliases to add FLOW-SEQUENCE-START or FLOW-MAPPING-START token.
alias fetchFlowCollectionStart!(TokenID.FlowSequenceStart) fetchFlowSequenceStart; alias fetchFlowCollectionStart!(TokenID.FlowSequenceStart) fetchFlowSequenceStart;
alias fetchFlowCollectionStart!(TokenID.FlowMappingStart) fetchFlowMappingStart; alias fetchFlowCollectionStart!(TokenID.FlowMappingStart) fetchFlowMappingStart;
///Add FLOW-SEQUENCE-START or FLOW-MAPPING-START token. /// Add FLOW-SEQUENCE-START or FLOW-MAPPING-START token.
void fetchFlowCollectionEnd(TokenID id)() @safe void fetchFlowCollectionEnd(TokenID id)() @safe
{ {
//Reset possible simple key on the current level. // Reset possible simple key on the current level.
removePossibleSimpleKey(); removePossibleSimpleKey();
//No simple keys after ']' and '}'. // No simple keys after ']' and '}'.
allowSimpleKey_ = false; allowSimpleKey_ = false;
--flowLevel_; --flowLevel_;
@ -555,16 +531,16 @@ final class Scanner
tokens_.push(simpleToken!id(startMark, reader_.mark)); tokens_.push(simpleToken!id(startMark, reader_.mark));
} }
///Aliases to add FLOW-SEQUENCE-START or FLOW-MAPPING-START token/ /// Aliases to add FLOW-SEQUENCE-START or FLOW-MAPPING-START token/
alias fetchFlowCollectionEnd!(TokenID.FlowSequenceEnd) fetchFlowSequenceEnd; alias fetchFlowCollectionEnd!(TokenID.FlowSequenceEnd) fetchFlowSequenceEnd;
alias fetchFlowCollectionEnd!(TokenID.FlowMappingEnd) fetchFlowMappingEnd; alias fetchFlowCollectionEnd!(TokenID.FlowMappingEnd) fetchFlowMappingEnd;
///Add FLOW-ENTRY token; /// Add FLOW-ENTRY token;
void fetchFlowEntry() @safe void fetchFlowEntry() @safe
{ {
//Reset possible simple key on the current level. // Reset possible simple key on the current level.
removePossibleSimpleKey(); removePossibleSimpleKey();
//Simple keys are allowed after ','. // Simple keys are allowed after ','.
allowSimpleKey_ = true; allowSimpleKey_ = true;
Mark startMark = reader_.mark; Mark startMark = reader_.mark;
@ -572,12 +548,10 @@ final class Scanner
tokens_.push(flowEntryToken(startMark, reader_.mark)); tokens_.push(flowEntryToken(startMark, reader_.mark));
} }
/** /// Additional checks used in block context in fetchBlockEntry and fetchKey.
* Additional checks used in block context in fetchBlockEntry and fetchKey. ///
* /// Params: type = String representing the token type we might need to add.
* Params: type = String representing the token type we might need to add. /// id = Token type we might need to add.
* id = Token type we might need to add.
*/
void blockChecks(string type, TokenID id)() @safe void blockChecks(string type, TokenID id)() @safe
{ {
//Are we allowed to start a key (not neccesarily a simple one)? //Are we allowed to start a key (not neccesarily a simple one)?
@ -590,17 +564,17 @@ final class Scanner
} }
} }
///Add BLOCK-ENTRY token. Might add BLOCK-SEQUENCE-START in the process. /// Add BLOCK-ENTRY token. Might add BLOCK-SEQUENCE-START in the process.
void fetchBlockEntry() @safe void fetchBlockEntry() @safe
{ {
if(flowLevel_ == 0){blockChecks!("Sequence", TokenID.BlockSequenceStart)();} if(flowLevel_ == 0) { blockChecks!("Sequence", TokenID.BlockSequenceStart)(); }
//It's an error for the block entry to occur in the flow context, // It's an error for the block entry to occur in the flow context,
//but we let the parser detect this. // but we let the parser detect this.
//Reset possible simple key on the current level. // Reset possible simple key on the current level.
removePossibleSimpleKey(); removePossibleSimpleKey();
//Simple keys are allowed after '-'. // Simple keys are allowed after '-'.
allowSimpleKey_ = true; allowSimpleKey_ = true;
Mark startMark = reader_.mark; Mark startMark = reader_.mark;
@ -608,14 +582,14 @@ final class Scanner
tokens_.push(blockEntryToken(startMark, reader_.mark)); tokens_.push(blockEntryToken(startMark, reader_.mark));
} }
///Add KEY token. Might add BLOCK-MAPPING-START in the process. /// Add KEY token. Might add BLOCK-MAPPING-START in the process.
void fetchKey() @safe void fetchKey() @safe
{ {
if(flowLevel_ == 0){blockChecks!("Mapping", TokenID.BlockMappingStart)();} if(flowLevel_ == 0) { blockChecks!("Mapping", TokenID.BlockMappingStart)(); }
//Reset possible simple key on the current level. // Reset possible simple key on the current level.
removePossibleSimpleKey(); removePossibleSimpleKey();
//Simple keys are allowed after '?' in the block context. // Simple keys are allowed after '?' in the block context.
allowSimpleKey_ = (flowLevel_ == 0); allowSimpleKey_ = (flowLevel_ == 0);
Mark startMark = reader_.mark; Mark startMark = reader_.mark;
@ -623,7 +597,7 @@ final class Scanner
tokens_.push(keyToken(startMark, reader_.mark)); tokens_.push(keyToken(startMark, reader_.mark));
} }
///Add VALUE token. Might add KEY and/or BLOCK-MAPPING-START in the process. /// Add VALUE token. Might add KEY and/or BLOCK-MAPPING-START in the process.
void fetchValue() @safe void fetchValue() @safe
{ {
//Do we determine a simple key? //Do we determine a simple key?
@ -637,52 +611,52 @@ final class Scanner
assert(idx >= 0); assert(idx >= 0);
//Add KEY. // Add KEY.
//Manually inserting since tokens are immutable (need linked list). // Manually inserting since tokens are immutable (need linked list).
tokens_.insert(keyToken(keyMark, keyMark), idx); tokens_.insert(keyToken(keyMark, keyMark), idx);
//If this key starts a new block mapping, we need to add BLOCK-MAPPING-START. // If this key starts a new block mapping, we need to add BLOCK-MAPPING-START.
if(flowLevel_ == 0 && addIndent(key.column)) if(flowLevel_ == 0 && addIndent(key.column))
{ {
tokens_.insert(blockMappingStartToken(keyMark, keyMark), idx); tokens_.insert(blockMappingStartToken(keyMark, keyMark), idx);
} }
//There cannot be two simple keys in a row. // There cannot be two simple keys in a row.
allowSimpleKey_ = false; allowSimpleKey_ = false;
} }
//Part of a complex key // Part of a complex key
else else
{ {
//We can start a complex value if and only if we can start a simple key. // We can start a complex value if and only if we can start a simple key.
enforce(flowLevel_ > 0 || allowSimpleKey_, enforce(flowLevel_ > 0 || allowSimpleKey_,
new Error("Mapping values are not allowed here", reader_.mark)); new Error("Mapping values are not allowed here", reader_.mark));
//If this value starts a new block mapping, we need to add // If this value starts a new block mapping, we need to add
//BLOCK-MAPPING-START. It'll be detected as an error later by the parser. // BLOCK-MAPPING-START. It'll be detected as an error later by the parser.
if(flowLevel_ == 0 && addIndent(reader_.column)) if(flowLevel_ == 0 && addIndent(reader_.column))
{ {
tokens_.push(blockMappingStartToken(reader_.mark, reader_.mark)); tokens_.push(blockMappingStartToken(reader_.mark, reader_.mark));
} }
//Reset possible simple key on the current level. // Reset possible simple key on the current level.
removePossibleSimpleKey(); removePossibleSimpleKey();
//Simple keys are allowed after ':' in the block context. // Simple keys are allowed after ':' in the block context.
allowSimpleKey_ = (flowLevel_ == 0); allowSimpleKey_ = (flowLevel_ == 0);
} }
//Add VALUE. // Add VALUE.
Mark startMark = reader_.mark; Mark startMark = reader_.mark;
reader_.forward(); reader_.forward();
tokens_.push(valueToken(startMark, reader_.mark)); tokens_.push(valueToken(startMark, reader_.mark));
} }
///Add ALIAS or ANCHOR token. /// Add ALIAS or ANCHOR token.
void fetchAnchor_(TokenID id)() @trusted void fetchAnchor_(TokenID id)() @trusted
if(id == TokenID.Alias || id == TokenID.Anchor) if(id == TokenID.Alias || id == TokenID.Anchor)
{ {
//ALIAS/ANCHOR could be a simple key. // ALIAS/ANCHOR could be a simple key.
savePossibleSimpleKey(); savePossibleSimpleKey();
//No simple keys after ALIAS/ANCHOR. // No simple keys after ALIAS/ANCHOR.
allowSimpleKey_ = false; allowSimpleKey_ = false;
const anchor = scanAnchor(id); const anchor = scanAnchor(id);
@ -690,11 +664,11 @@ final class Scanner
tokens_.push(anchor); tokens_.push(anchor);
} }
///Aliases to add ALIAS or ANCHOR token. /// Aliases to add ALIAS or ANCHOR token.
alias fetchAnchor_!(TokenID.Alias) fetchAlias; alias fetchAnchor_!(TokenID.Alias) fetchAlias;
alias fetchAnchor_!(TokenID.Anchor) fetchAnchor; alias fetchAnchor_!(TokenID.Anchor) fetchAnchor;
///Add TAG token. /// Add TAG token.
void fetchTag() @trusted void fetchTag() @trusted
{ {
//TAG could start a simple key. //TAG could start a simple key.
@ -706,13 +680,13 @@ final class Scanner
throwIfError(); throwIfError();
} }
///Add block SCALAR token. /// Add block SCALAR token.
void fetchBlockScalar(ScalarStyle style)() @trusted void fetchBlockScalar(ScalarStyle style)() @trusted
if(style == ScalarStyle.Literal || style == ScalarStyle.Folded) if(style == ScalarStyle.Literal || style == ScalarStyle.Folded)
{ {
//Reset possible simple key on the current level. // Reset possible simple key on the current level.
removePossibleSimpleKey(); removePossibleSimpleKey();
//A simple key may follow a block scalar. // A simple key may follow a block scalar.
allowSimpleKey_ = true; allowSimpleKey_ = true;
auto blockScalar = scanBlockScalar(style); auto blockScalar = scanBlockScalar(style);
@ -1567,7 +1541,7 @@ final class Scanner
size_t length = 0; size_t length = 0;
// This is an optimized way of writing: // This is an optimized way of writing:
// while(!search.canFind(reader_.peek(length))){++length;} // while(!search.canFind(reader_.peek(length))) { ++length; }
outer: for(;;) outer: for(;;)
{ {
const slice = reader_.slice(length, length + 32); const slice = reader_.slice(length, length + 32);
@ -1912,7 +1886,8 @@ final class Scanner
/// characters into that slice. /// characters into that slice.
/// ///
/// In case of an error, error_ is set. Use throwIfError() to handle this. /// In case of an error, error_ is set. Use throwIfError() to handle this.
void scanTagURIToSlice(string name)(const Mark startMark) @trusted pure nothrow void scanTagURIToSlice(string name)(const Mark startMark)
@trusted pure nothrow // @nogc
{ {
// Note: we do not check if URI is well-formed. // Note: we do not check if URI is well-formed.
dchar c = reader_.peek(); dchar c = reader_.peek();