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Cameron Ross 2019-01-24 02:53:40 -04:00 committed by Basile-z
parent aa9b4c8c2b
commit bc7e7f9593
3 changed files with 149 additions and 132 deletions
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15
source/dyaml/loader.d
View file

@ -249,14 +249,14 @@ struct Loader
return currentNode; return currentNode;
} }
// Scan and return all tokens. Used for debugging. // Scan and return all tokens. Used for debugging.
Token[] scan() @safe const(Token)[] scan() @safe
{ {
try try
{ {
Token[] result; const(Token)[] result;
while(scanner_.checkToken()) foreach (token; scanner_)
{ {
result ~= scanner_.getToken(); result ~= token;
} }
return result; return result;
} }
@ -270,9 +270,12 @@ struct Loader
// Scan all tokens, throwing them away. Used for benchmarking. // Scan all tokens, throwing them away. Used for benchmarking.
void scanBench() @safe void scanBench() @safe
{ {
try while(scanner_.checkToken()) try
{ {
scanner_.getToken(); while(!scanner_.empty)
{
scanner_.popFront();
}
} }
catch(YAMLException e) catch(YAMLException e)
{ {

213
source/dyaml/parser.d
View file

@ -222,7 +222,8 @@ final class Parser
///Parse stream start. ///Parse stream start.
Event parseStreamStart() @safe Event parseStreamStart() @safe
{ {
const token = scanner_.getToken(); const token = scanner_.front;
scanner_.popFront();
state_ = &parseImplicitDocumentStart; state_ = &parseImplicitDocumentStart;
return streamStartEvent(token.startMark, token.endMark); return streamStartEvent(token.startMark, token.endMark);
} }
@ -231,11 +232,11 @@ final class Parser
Event parseImplicitDocumentStart() @safe Event parseImplicitDocumentStart() @safe
{ {
// Parse an implicit document. // Parse an implicit document.
if(!scanner_.checkToken(TokenID.directive, TokenID.documentStart, if(!scanner_.front.id.among!(TokenID.directive, TokenID.documentStart,
TokenID.streamEnd)) TokenID.streamEnd))
{ {
tagDirectives_ = defaultTagDirectives_; tagDirectives_ = defaultTagDirectives_;
const token = scanner_.peekToken(); const token = scanner_.front;
pushState(&parseDocumentEnd); pushState(&parseDocumentEnd);
state_ = &parseBlockNode; state_ = &parseBlockNode;
@ -249,20 +250,24 @@ final class Parser
Event parseDocumentStart() @trusted Event parseDocumentStart() @trusted
{ {
//Parse any extra document end indicators. //Parse any extra document end indicators.
while(scanner_.checkToken(TokenID.documentEnd)){scanner_.getToken();} while(scanner_.front.id == TokenID.documentEnd)
{
scanner_.popFront();
}
//Parse an explicit document. //Parse an explicit document.
if(!scanner_.checkToken(TokenID.streamEnd)) if(scanner_.front.id != TokenID.streamEnd)
{ {
const startMark = scanner_.peekToken().startMark; const startMark = scanner_.front.startMark;
auto tagDirectives = processDirectives(); auto tagDirectives = processDirectives();
enforce(scanner_.checkToken(TokenID.documentStart), enforce(scanner_.front.id == TokenID.documentStart,
new ParserException("Expected document start but found " ~ new ParserException("Expected document start but found " ~
scanner_.peekToken().idString, scanner_.front.idString,
scanner_.peekToken().startMark)); scanner_.front.startMark));
const endMark = scanner_.getToken().endMark; const endMark = scanner_.front.endMark;
scanner_.popFront();
pushState(&parseDocumentEnd); pushState(&parseDocumentEnd);
state_ = &parseDocumentContent; state_ = &parseDocumentContent;
return documentStartEvent(startMark, endMark, true, YAMLVersion_, tagDirectives); return documentStartEvent(startMark, endMark, true, YAMLVersion_, tagDirectives);
@ -270,7 +275,8 @@ final class Parser
else else
{ {
//Parse the end of the stream. //Parse the end of the stream.
const token = scanner_.getToken(); const token = scanner_.front;
scanner_.popFront();
assert(states_.data.length == 0); assert(states_.data.length == 0);
assert(marks_.data.length == 0); assert(marks_.data.length == 0);
state_ = null; state_ = null;
@ -281,9 +287,14 @@ final class Parser
///Parse document end (explicit or implicit). ///Parse document end (explicit or implicit).
Event parseDocumentEnd() @safe Event parseDocumentEnd() @safe
{ {
Mark startMark = scanner_.peekToken().startMark; Mark startMark = scanner_.front.startMark;
const bool explicit = scanner_.checkToken(TokenID.documentEnd); const bool explicit = scanner_.front.id == TokenID.documentEnd;
Mark endMark = explicit ? scanner_.getToken().endMark : startMark; Mark endMark = startMark;
if (explicit)
{
endMark = scanner_.front.endMark;
scanner_.popFront();
}
state_ = &parseDocumentStart; state_ = &parseDocumentStart;
@ -293,11 +304,11 @@ final class Parser
///Parse document content. ///Parse document content.
Event parseDocumentContent() @safe Event parseDocumentContent() @safe
{ {
if(scanner_.checkToken(TokenID.directive, TokenID.documentStart, if(scanner_.front.id.among!(TokenID.directive, TokenID.documentStart,
TokenID.documentEnd, TokenID.streamEnd)) TokenID.documentEnd, TokenID.streamEnd))
{ {
state_ = popState(); state_ = popState();
return processEmptyScalar(scanner_.peekToken().startMark); return processEmptyScalar(scanner_.front.startMark);
} }
return parseBlockNode(); return parseBlockNode();
} }
@ -310,9 +321,10 @@ final class Parser
tagDirectives_.length = 0; tagDirectives_.length = 0;
// Process directives. // Process directives.
while(scanner_.checkToken(TokenID.directive)) while(scanner_.front.id == TokenID.directive)
{ {
const token = scanner_.getToken(); const token = scanner_.front;
scanner_.popFront();
string value = token.value.idup; string value = token.value.idup;
if(token.directive == DirectiveType.yaml) if(token.directive == DirectiveType.yaml)
{ {
@ -382,9 +394,10 @@ final class Parser
const Flag!"indentlessSequence" indentlessSequence = No.indentlessSequence) const Flag!"indentlessSequence" indentlessSequence = No.indentlessSequence)
@trusted @trusted
{ {
if(scanner_.checkToken(TokenID.alias_)) if(scanner_.front.id == TokenID.alias_)
{ {
const token = scanner_.getToken(); const token = scanner_.front;
scanner_.popFront();
state_ = popState(); state_ = popState();
return aliasEvent(token.startMark, token.endMark, return aliasEvent(token.startMark, token.endMark,
cast(string)token.value); cast(string)token.value);
@ -400,9 +413,10 @@ final class Parser
//Get anchor/tag if detected. Return false otherwise. //Get anchor/tag if detected. Return false otherwise.
bool get(const TokenID id, const Flag!"first" first, ref string target) @safe bool get(const TokenID id, const Flag!"first" first, ref string target) @safe
{ {
if(!scanner_.checkToken(id)){return false;} if(scanner_.front.id != id){return false;}
invalidMarks = false; invalidMarks = false;
const token = scanner_.getToken(); const token = scanner_.front;
scanner_.popFront();
if(first){startMark = token.startMark;} if(first){startMark = token.startMark;}
if(id == TokenID.tag) if(id == TokenID.tag)
{ {
@ -422,24 +436,25 @@ final class Parser
if(invalidMarks) if(invalidMarks)
{ {
startMark = endMark = scanner_.peekToken().startMark; startMark = endMark = scanner_.front.startMark;
} }
bool implicit = (tag is null || tag == "!"); bool implicit = (tag is null || tag == "!");
if(indentlessSequence && scanner_.checkToken(TokenID.blockEntry)) if(indentlessSequence && scanner_.front.id == TokenID.blockEntry)
{ {
state_ = &parseIndentlessSequenceEntry; state_ = &parseIndentlessSequenceEntry;
return sequenceStartEvent return sequenceStartEvent
(startMark, scanner_.peekToken().endMark, anchor, (startMark, scanner_.front.endMark, anchor,
tag, implicit, CollectionStyle.block); tag, implicit, CollectionStyle.block);
} }
if(scanner_.checkToken(TokenID.scalar)) if(scanner_.front.id == TokenID.scalar)
{ {
auto token = scanner_.getToken(); auto token = scanner_.front;
scanner_.popFront();
auto value = token.style == ScalarStyle.doubleQuoted auto value = token.style == ScalarStyle.doubleQuoted
? handleDoubleQuotedScalarEscapes(token.value) ? handleDoubleQuotedScalarEscapes(token.value.dup)
: cast(string)token.value; : cast(string)token.value;
implicit = (token.style == ScalarStyle.plain && tag is null) || tag == "!"; implicit = (token.style == ScalarStyle.plain && tag is null) || tag == "!";
@ -448,33 +463,33 @@ final class Parser
implicit, value, token.style); implicit, value, token.style);
} }
if(scanner_.checkToken(TokenID.flowSequenceStart)) if(scanner_.front.id == TokenID.flowSequenceStart)
{ {
endMark = scanner_.peekToken().endMark; endMark = scanner_.front.endMark;
state_ = &parseFlowSequenceEntry!(Yes.first); state_ = &parseFlowSequenceEntry!(Yes.first);
return sequenceStartEvent(startMark, endMark, anchor, tag, return sequenceStartEvent(startMark, endMark, anchor, tag,
implicit, CollectionStyle.flow); implicit, CollectionStyle.flow);
} }
if(scanner_.checkToken(TokenID.flowMappingStart)) if(scanner_.front.id == TokenID.flowMappingStart)
{ {
endMark = scanner_.peekToken().endMark; endMark = scanner_.front.endMark;
state_ = &parseFlowMappingKey!(Yes.first); state_ = &parseFlowMappingKey!(Yes.first);
return mappingStartEvent(startMark, endMark, anchor, tag, return mappingStartEvent(startMark, endMark, anchor, tag,
implicit, CollectionStyle.flow); implicit, CollectionStyle.flow);
} }
if(block && scanner_.checkToken(TokenID.blockSequenceStart)) if(block && scanner_.front.id == TokenID.blockSequenceStart)
{ {
endMark = scanner_.peekToken().endMark; endMark = scanner_.front.endMark;
state_ = &parseBlockSequenceEntry!(Yes.first); state_ = &parseBlockSequenceEntry!(Yes.first);
return sequenceStartEvent(startMark, endMark, anchor, tag, return sequenceStartEvent(startMark, endMark, anchor, tag,
implicit, CollectionStyle.block); implicit, CollectionStyle.block);
} }
if(block && scanner_.checkToken(TokenID.blockMappingStart)) if(block && scanner_.front.id == TokenID.blockMappingStart)
{ {
endMark = scanner_.peekToken().endMark; endMark = scanner_.front.endMark;
state_ = &parseBlockMappingKey!(Yes.first); state_ = &parseBlockMappingKey!(Yes.first);
return mappingStartEvent(startMark, endMark, anchor, tag, return mappingStartEvent(startMark, endMark, anchor, tag,
implicit, CollectionStyle.block); implicit, CollectionStyle.block);
@ -492,7 +507,7 @@ final class Parser
implicit , ""); implicit , "");
} }
const token = scanner_.peekToken(); const token = scanner_.front;
throw new ParserException("While parsing a " ~ (block ? "block" : "flow") ~ " node", throw new ParserException("While parsing a " ~ (block ? "block" : "flow") ~ " node",
startMark, "expected node content, but found: " startMark, "expected node content, but found: "
~ token.idString, token.startMark); ~ token.idString, token.startMark);
@ -620,12 +635,17 @@ final class Parser
///Parse an entry of a block sequence. If first is true, this is the first entry. ///Parse an entry of a block sequence. If first is true, this is the first entry.
Event parseBlockSequenceEntry(Flag!"first" first)() @safe Event parseBlockSequenceEntry(Flag!"first" first)() @safe
{ {
static if(first){pushMark(scanner_.getToken().startMark);} static if(first)
if(scanner_.checkToken(TokenID.blockEntry))
{ {
const token = scanner_.getToken(); pushMark(scanner_.front.startMark);
if(!scanner_.checkToken(TokenID.blockEntry, TokenID.blockEnd)) scanner_.popFront();
}
if(scanner_.front.id == TokenID.blockEntry)
{
const token = scanner_.front;
scanner_.popFront();
if(!scanner_.front.id.among!(TokenID.blockEntry, TokenID.blockEnd))
{ {
pushState(&parseBlockSequenceEntry!(No.first)); pushState(&parseBlockSequenceEntry!(No.first));
return parseBlockNode(); return parseBlockNode();
@ -635,9 +655,9 @@ final class Parser
return processEmptyScalar(token.endMark); return processEmptyScalar(token.endMark);
} }
if(!scanner_.checkToken(TokenID.blockEnd)) if(scanner_.front.id != TokenID.blockEnd)
{ {
const token = scanner_.peekToken(); const token = scanner_.front;
throw new ParserException("While parsing a block collection", marks_.data.back, throw new ParserException("While parsing a block collection", marks_.data.back,
"expected block end, but found " ~ token.idString, "expected block end, but found " ~ token.idString,
token.startMark); token.startMark);
@ -645,7 +665,8 @@ final class Parser
state_ = popState(); state_ = popState();
popMark(); popMark();
const token = scanner_.getToken(); const token = scanner_.front;
scanner_.popFront();
return sequenceEndEvent(token.startMark, token.endMark); return sequenceEndEvent(token.startMark, token.endMark);
} }
@ -654,11 +675,12 @@ final class Parser
///Parse an entry of an indentless sequence. ///Parse an entry of an indentless sequence.
Event parseIndentlessSequenceEntry() @safe Event parseIndentlessSequenceEntry() @safe
{ {
if(scanner_.checkToken(TokenID.blockEntry)) if(scanner_.front.id == TokenID.blockEntry)
{ {
const token = scanner_.getToken(); const token = scanner_.front;
scanner_.popFront();
if(!scanner_.checkToken(TokenID.blockEntry, TokenID.key, if(!scanner_.front.id.among!(TokenID.blockEntry, TokenID.key,
TokenID.value, TokenID.blockEnd)) TokenID.value, TokenID.blockEnd))
{ {
pushState(&parseIndentlessSequenceEntry); pushState(&parseIndentlessSequenceEntry);
@ -670,7 +692,7 @@ final class Parser
} }
state_ = popState(); state_ = popState();
const token = scanner_.peekToken(); const token = scanner_.front;
return sequenceEndEvent(token.startMark, token.endMark); return sequenceEndEvent(token.startMark, token.endMark);
} }
@ -684,13 +706,18 @@ final class Parser
///Parse a key in a block mapping. If first is true, this is the first key. ///Parse a key in a block mapping. If first is true, this is the first key.
Event parseBlockMappingKey(Flag!"first" first)() @safe Event parseBlockMappingKey(Flag!"first" first)() @safe
{ {
static if(first){pushMark(scanner_.getToken().startMark);} static if(first)
if(scanner_.checkToken(TokenID.key))
{ {
const token = scanner_.getToken(); pushMark(scanner_.front.startMark);
scanner_.popFront();
}
if(!scanner_.checkToken(TokenID.key, TokenID.value, TokenID.blockEnd)) if(scanner_.front.id == TokenID.key)
{
const token = scanner_.front;
scanner_.popFront();
if(!scanner_.front.id.among!(TokenID.key, TokenID.value, TokenID.blockEnd))
{ {
pushState(&parseBlockMappingValue); pushState(&parseBlockMappingValue);
return parseBlockNodeOrIndentlessSequence(); return parseBlockNodeOrIndentlessSequence();
@ -700,9 +727,9 @@ final class Parser
return processEmptyScalar(token.endMark); return processEmptyScalar(token.endMark);
} }
if(!scanner_.checkToken(TokenID.blockEnd)) if(scanner_.front.id != TokenID.blockEnd)
{ {
const token = scanner_.peekToken(); const token = scanner_.front;
throw new ParserException("While parsing a block mapping", marks_.data.back, throw new ParserException("While parsing a block mapping", marks_.data.back,
"expected block end, but found: " ~ token.idString, "expected block end, but found: " ~ token.idString,
token.startMark); token.startMark);
@ -710,18 +737,20 @@ final class Parser
state_ = popState(); state_ = popState();
popMark(); popMark();
const token = scanner_.getToken(); const token = scanner_.front;
scanner_.popFront();
return mappingEndEvent(token.startMark, token.endMark); return mappingEndEvent(token.startMark, token.endMark);
} }
///Parse a value in a block mapping. ///Parse a value in a block mapping.
Event parseBlockMappingValue() @safe Event parseBlockMappingValue() @safe
{ {
if(scanner_.checkToken(TokenID.value)) if(scanner_.front.id == TokenID.value)
{ {
const token = scanner_.getToken(); const token = scanner_.front;
scanner_.popFront();
if(!scanner_.checkToken(TokenID.key, TokenID.value, TokenID.blockEnd)) if(!scanner_.front.id.among!(TokenID.key, TokenID.value, TokenID.blockEnd))
{ {
pushState(&parseBlockMappingKey!(No.first)); pushState(&parseBlockMappingKey!(No.first));
return parseBlockNodeOrIndentlessSequence(); return parseBlockNodeOrIndentlessSequence();
@ -732,7 +761,7 @@ final class Parser
} }
state_= &parseBlockMappingKey!(No.first); state_= &parseBlockMappingKey!(No.first);
return processEmptyScalar(scanner_.peekToken().startMark); return processEmptyScalar(scanner_.front.startMark);
} }
/** /**
@ -751,40 +780,45 @@ final class Parser
///Parse an entry in a flow sequence. If first is true, this is the first entry. ///Parse an entry in a flow sequence. If first is true, this is the first entry.
Event parseFlowSequenceEntry(Flag!"first" first)() @safe Event parseFlowSequenceEntry(Flag!"first" first)() @safe
{ {
static if(first){pushMark(scanner_.getToken().startMark);} static if(first)
{
pushMark(scanner_.front.startMark);
scanner_.popFront();
}
if(!scanner_.checkToken(TokenID.flowSequenceEnd)) if(scanner_.front.id != TokenID.flowSequenceEnd)
{ {
static if(!first) static if(!first)
{ {
if(scanner_.checkToken(TokenID.flowEntry)) if(scanner_.front.id == TokenID.flowEntry)
{ {
scanner_.getToken(); scanner_.popFront();
} }
else else
{ {
const token = scanner_.peekToken(); const token = scanner_.front;
throw new ParserException("While parsing a flow sequence", marks_.data.back, throw new ParserException("While parsing a flow sequence", marks_.data.back,
"expected ',' or ']', but got: " ~ "expected ',' or ']', but got: " ~
token.idString, token.startMark); token.idString, token.startMark);
} }
} }
if(scanner_.checkToken(TokenID.key)) if(scanner_.front.id == TokenID.key)
{ {
const token = scanner_.peekToken(); const token = scanner_.front;
state_ = &parseFlowSequenceEntryMappingKey; state_ = &parseFlowSequenceEntryMappingKey;
return mappingStartEvent(token.startMark, token.endMark, return mappingStartEvent(token.startMark, token.endMark,
null, null, true, CollectionStyle.flow); null, null, true, CollectionStyle.flow);
} }
else if(!scanner_.checkToken(TokenID.flowSequenceEnd)) else if(scanner_.front.id != TokenID.flowSequenceEnd)
{ {
pushState(&parseFlowSequenceEntry!(No.first)); pushState(&parseFlowSequenceEntry!(No.first));
return parseFlowNode(); return parseFlowNode();
} }
} }
const token = scanner_.getToken(); const token = scanner_.front;
scanner_.popFront();
state_ = popState(); state_ = popState();
popMark(); popMark();
return sequenceEndEvent(token.startMark, token.endMark); return sequenceEndEvent(token.startMark, token.endMark);
@ -793,9 +827,10 @@ final class Parser
///Parse a key in flow context. ///Parse a key in flow context.
Event parseFlowKey(in Event delegate() @safe nextState) @safe Event parseFlowKey(in Event delegate() @safe nextState) @safe
{ {
const token = scanner_.getToken(); const token = scanner_.front;
scanner_.popFront();
if(!scanner_.checkToken(TokenID.value, TokenID.flowEntry, if(!scanner_.front.id.among!(TokenID.value, TokenID.flowEntry,
TokenID.flowSequenceEnd)) TokenID.flowSequenceEnd))
{ {
pushState(nextState); pushState(nextState);
@ -816,10 +851,11 @@ final class Parser
Event parseFlowValue(TokenID checkId, in Event delegate() @safe nextState) Event parseFlowValue(TokenID checkId, in Event delegate() @safe nextState)
@safe @safe
{ {
if(scanner_.checkToken(TokenID.value)) if(scanner_.front.id == TokenID.value)
{ {
const token = scanner_.getToken(); const token = scanner_.front;
if(!scanner_.checkToken(TokenID.flowEntry, checkId)) scanner_.popFront();
if(!scanner_.front.id.among(TokenID.flowEntry, checkId))
{ {
pushState(nextState); pushState(nextState);
return parseFlowNode(); return parseFlowNode();
@ -830,7 +866,7 @@ final class Parser
} }
state_ = nextState; state_ = nextState;
return processEmptyScalar(scanner_.peekToken().startMark); return processEmptyScalar(scanner_.front.startMark);
} }
///Parse a mapping value in an entry in a flow sequence. ///Parse a mapping value in an entry in a flow sequence.
@ -844,7 +880,7 @@ final class Parser
Event parseFlowSequenceEntryMappingEnd() @safe Event parseFlowSequenceEntryMappingEnd() @safe
{ {
state_ = &parseFlowSequenceEntry!(No.first); state_ = &parseFlowSequenceEntry!(No.first);
const token = scanner_.peekToken(); const token = scanner_.front;
return mappingEndEvent(token.startMark, token.startMark); return mappingEndEvent(token.startMark, token.startMark);
} }
@ -859,38 +895,43 @@ final class Parser
///Parse a key in a flow mapping. ///Parse a key in a flow mapping.
Event parseFlowMappingKey(Flag!"first" first)() @safe Event parseFlowMappingKey(Flag!"first" first)() @safe
{ {
static if(first){pushMark(scanner_.getToken().startMark);} static if(first)
{
pushMark(scanner_.front.startMark);
scanner_.popFront();
}
if(!scanner_.checkToken(TokenID.flowMappingEnd)) if(scanner_.front.id != TokenID.flowMappingEnd)
{ {
static if(!first) static if(!first)
{ {
if(scanner_.checkToken(TokenID.flowEntry)) if(scanner_.front.id == TokenID.flowEntry)
{ {
scanner_.getToken(); scanner_.popFront();
} }
else else
{ {
const token = scanner_.peekToken(); const token = scanner_.front;
throw new ParserException("While parsing a flow mapping", marks_.data.back, throw new ParserException("While parsing a flow mapping", marks_.data.back,
"expected ',' or '}', but got: " ~ "expected ',' or '}', but got: " ~
token.idString, token.startMark); token.idString, token.startMark);
} }
} }
if(scanner_.checkToken(TokenID.key)) if(scanner_.front.id == TokenID.key)
{ {
return parseFlowKey(&parseFlowMappingValue); return parseFlowKey(&parseFlowMappingValue);
} }
if(!scanner_.checkToken(TokenID.flowMappingEnd)) if(scanner_.front.id != TokenID.flowMappingEnd)
{ {
pushState(&parseFlowMappingEmptyValue); pushState(&parseFlowMappingEmptyValue);
return parseFlowNode(); return parseFlowNode();
} }
} }
const token = scanner_.getToken(); const token = scanner_.front;
scanner_.popFront();
state_ = popState(); state_ = popState();
popMark(); popMark();
return mappingEndEvent(token.startMark, token.endMark); return mappingEndEvent(token.startMark, token.endMark);
@ -906,7 +947,7 @@ final class Parser
Event parseFlowMappingEmptyValue() @safe Event parseFlowMappingEmptyValue() @safe
{ {
state_ = &parseFlowMappingKey!(No.first); state_ = &parseFlowMappingKey!(No.first);
return processEmptyScalar(scanner_.peekToken().startMark); return processEmptyScalar(scanner_.front.startMark);
} }
///Return an empty scalar. ///Return an empty scalar.

53
source/dyaml/scanner.d
View file

@ -178,55 +178,28 @@ struct Scanner
fetchStreamStart(); fetchStreamStart();
} }
/// Check if the next token is one of specified types. /// Advance to the next token
/// void popFront() @safe
/// If no types are specified, checks if any tokens are left.
///
/// Params: ids = Token IDs to check for.
///
/// Returns: true if the next token is one of specified types, or if there are
/// any tokens left if no types specified, false otherwise.
bool checkToken(const TokenID[] ids ...) @safe
{ {
// Check if the next token is one of specified types. ++tokensTaken_;
while(needMoreTokens()) { fetchToken(); } tokens_.pop();
if(!tokens_.empty)
{
if(ids.length == 0) { return true; }
else
{
const nextId = tokens_.peek().id;
foreach(id; ids)
{
if(nextId == id) { return true; }
}
}
}
return false;
} }
/// Return the next token, but keep it in the queue. /// Return the current token
/// const(Token) front() @safe
/// Must not be called if there are no tokens left.
ref const(Token) peekToken() @safe
{ {
while(needMoreTokens) { fetchToken(); } enforce(!empty, "No token left to peek");
if(!tokens_.empty) { return tokens_.peek(); } return tokens_.peek();
assert(false, "No token left to peek");
} }
/// Return the next token, removing it from the queue. /// Return whether there are any more tokens left.
/// bool empty() @safe
/// Must not be called if there are no tokens left.
Token getToken() @safe
{ {
while(needMoreTokens){fetchToken();} while (needMoreTokens())
if(!tokens_.empty)
{ {
++tokensTaken_; fetchToken();
return tokens_.pop();
} }
assert(false, "No token left to get"); return tokens_.empty;
} }
private: private: