NimYAML/private/fastparse.nim

1532 lines
51 KiB
Nim

# NimYAML - YAML implementation in Nim
# (c) Copyright 2015 Felix Krause
#
# See the file "copying.txt", included in this
# distribution, for details about the copyright.
type
FastParseState = enum
fpInitial, fpBlockAfterObject, fpBlockAfterPlainScalar, fpBlockObjectStart,
fpExpectDocEnd, fpFlow, fpFlowAfterObject, fpAfterDocument
FastParseLevelKind = enum
fplUnknown, fplSequence, fplMapKey, fplMapValue, fplSinglePairKey,
fplSinglePairValue, fplScalar, fplDocument
ScalarType = enum
stFlow, stLiteral, stFolded
FastParseLevel = object
kind: FastParseLevelKind
indentation: int
LexedDirective = enum
ldYaml, ldTag, ldUnknown
YamlContext = enum
cBlock, cFlow
ChompType = enum
ctKeep, ctClip, ctStrip
const
space = {' ', '\t'}
lineEnd = {'\l', '\c', EndOfFile}
spaceOrLineEnd = {' ', '\t', '\l', '\c', EndOfFile}
digits = {'0'..'9'}
flowIndicators = {'[', ']', '{', '}', ','}
UTF8NextLine = toUTF8(0x85.Rune)
UTF8NonBreakingSpace = toUTF8(0xA0.Rune)
UTF8LineSeparator = toUTF8(0x2028.Rune)
UTF8ParagraphSeparator = toUTF8(0x2029.Rune)
UnknownIndentation = int.low
proc newYamlParser*(tagLib: TagLibrary = initExtendedTagLibrary(),
callback: WarningCallback = nil): YamlParser =
new(result)
result.tagLib = tagLib
result.callback = callback
proc getLineNumber*(p: YamlParser): int = p.lexer.lineNumber
proc getColNumber*(p: YamlParser): int = p.tokenstart + 1 # column is 1-based
proc getLineContent*(p: YamlParser, marker: bool = true): string =
result = p.lexer.getCurrentLine(false)
if marker:
result.add(repeat(' ', p.tokenstart) & "^\n")
template debug(message: string) {.dirty.} =
when defined(yamlDebug):
try: styledWriteLine(stdout, fgBlue, message)
except IOError: discard
template debugFail() {.dirty.} =
when not defined(release):
echo "internal error at line: ", instantiationInfo().line
assert(false)
template parserError(message: string) {.dirty.} =
var e = newException(YamlParserError, message)
e.line = p.lexer.lineNumber
e.column = p.tokenstart + 1
e.lineContent = p.getLineContent(true)
raise e
template lexerError(lx: BaseLexer, message: string) {.dirty.} =
var e = newException(YamlParserError, message)
e.line = lx.lineNumber
e.column = lx.bufpos + 1
e.lineContent = lx.getCurrentLine(false) &
repeat(' ', lx.getColNumber(lx.bufpos)) & "^\n"
raise e
template addMultiple(s: var string, c: char, num: int) =
for i in 1..num:
s.add(c)
template startContent() {.dirty.} = content.setLen(0)
template initLevel(k: FastParseLevelKind): FastParseLevel =
FastParseLevel(kind: k, indentation: UnknownIndentation)
template yieldEmptyScalar() {.dirty.} =
yield scalarEvent("", tag, anchor)
tag = yTagQuestionMark
anchor = yAnchorNone
template yieldShallowScalar(content: string) {.dirty.} =
var e = YamlStreamEvent(kind: yamlScalar, scalarTag: tag,
scalarAnchor: anchor)
shallowCopy(e.scalarContent, content)
yield e
template yieldLevelEnd() {.dirty.} =
case level.kind
of fplSequence: yield endSeqEvent()
of fplMapKey: yield endMapEvent()
of fplMapValue, fplSinglePairValue:
yieldEmptyScalar()
yield endMapEvent()
of fplScalar:
if scalarType != stFlow:
case chomp
of ctKeep:
if content.len == 0: newlines.inc(-1)
content.addMultiple('\l', newlines)
of ctClip:
if content.len != 0: content.add('\l')
of ctStrip: discard
yieldShallowScalar(content)
tag = yTagQuestionMark
anchor = yAnchorNone
of fplUnknown:
if ancestry.len > 1: yieldEmptyScalar() # don't yield scalar for empty doc
of fplSinglePairKey, fplDocument: debugFail()
template handleLineEnd(insideDocument: bool) {.dirty.} =
case p.lexer.buf[p.lexer.bufpos]
of '\l': p.lexer.bufpos = p.lexer.handleLF(p.lexer.bufpos)
of '\c': p.lexer.bufpos = p.lexer.handleCR(p.lexer.bufpos)
of EndOfFile:
when insideDocument: closeEverything()
return
else: discard
newlines.inc()
template handleObjectEnd(nextState: FastParseState) {.dirty.} =
level = ancestry.pop()
if level.kind == fplSinglePairValue:
yield endMapEvent()
level = ancestry.pop()
state = if level.kind == fplDocument: fpExpectDocEnd else: nextState
tag = yTagQuestionMark
anchor = yAnchorNone
case level.kind
of fplMapKey: level.kind = fplMapValue
of fplSinglePairKey: level.kind = fplSinglePairValue
of fplMapValue: level.kind = fplMapKey
of fplSequence, fplDocument: discard
of fplUnknown, fplScalar, fplSinglePairValue: debugFail()
template handleObjectStart(k: YamlStreamEventKind, single: bool = false)
{.dirty.} =
assert(level.kind == fplUnknown)
when k == yamlStartMap:
yield startMapEvent(tag, anchor)
if single:
debug("started single-pair map at " &
(if level.indentation == UnknownIndentation: $indentation else:
$level.indentation))
level.kind = fplSinglePairKey
else:
debug("started map at " &
(if level.indentation == UnknownIndentation: $indentation else:
$level.indentation))
level.kind = fplMapKey
else:
yield startSeqEvent(tag, anchor)
debug("started sequence at " &
(if level.indentation == UnknownIndentation: $indentation else:
$level.indentation))
level.kind = fplSequence
tag = yTagQuestionMark
anchor = yAnchorNone
if level.indentation == UnknownIndentation: level.indentation = indentation
ancestry.add(level)
level = initLevel(fplUnknown)
template closeMoreIndentedLevels(atSequenceItem: bool = false) {.dirty.} =
while level.kind != fplDocument:
let parent = ancestry[ancestry.high]
if parent.indentation >= indentation:
when atSequenceItem:
if (indentation == level.indentation and level.kind == fplSequence) or
(indentation == parent.indentation and level.kind == fplUnknown and
parent.kind != fplSequence):
break
debug("Closing because parent.indentation (" & $parent.indentation &
") >= indentation(" & $indentation & ")")
yieldLevelEnd()
handleObjectEnd(state)
else: break
if level.kind == fplDocument: state = fpExpectDocEnd
template closeEverything() {.dirty.} =
indentation = 0
closeMoreIndentedLevels()
case level.kind
of fplUnknown: discard ancestry.pop()
of fplDocument: discard
else:
yieldLevelEnd()
discard ancestry.pop()
yield endDocEvent()
template handleBlockSequenceIndicator() {.dirty.} =
startToken()
case level.kind
of fplUnknown: handleObjectStart(yamlStartSeq)
of fplSequence:
if level.indentation != indentation:
parserError("Invalid indentation of block sequence indicator")
ancestry.add(level)
level = initLevel(fplUnknown)
else: parserError("Illegal sequence item in map")
p.lexer.skipWhitespace()
indentation = p.lexer.getColNumber(p.lexer.bufpos)
template handleMapKeyIndicator() {.dirty.} =
startToken()
case level.kind
of fplUnknown: handleObjectStart(yamlStartMap)
of fplMapValue:
if level.indentation != indentation:
parserError("Invalid indentation of map key indicator")
yield scalarEvent("", yTagQuestionMark, yAnchorNone)
level.kind = fplMapKey
ancestry.add(level)
level = initLevel(fplUnknown)
of fplMapKey:
if level.indentation != indentation:
parserError("Invalid indentation of map key indicator")
ancestry.add(level)
level = initLevel(fplUnknown)
of fplSequence:
parserError("Unexpected map key indicator (expected '- ')")
of fplScalar:
parserError("Unexpected map key indicator (expected multiline scalar end)")
of fplSinglePairKey, fplSinglePairValue, fplDocument: debugFail()
p.lexer.skipWhitespace()
indentation = p.lexer.getColNumber(p.lexer.bufpos)
template handleMapValueIndicator() {.dirty.} =
startToken()
case level.kind
of fplUnknown:
if level.indentation == UnknownIndentation:
handleObjectStart(yamlStartMap)
yield scalarEvent("", yTagQuestionMark, yAnchorNone)
else: yieldEmptyScalar()
ancestry[ancestry.high].kind = fplMapValue
of fplMapKey:
if level.indentation != indentation:
parserError("Invalid indentation of map key indicator")
yield scalarEvent("", yTagQuestionMark, yAnchorNone)
level.kind = fplMapValue
ancestry.add(level)
level = initLevel(fplUnknown)
of fplMapValue:
if level.indentation != indentation:
parserError("Invalid indentation of map key indicator")
ancestry.add(level)
level = initLevel(fplUnknown)
of fplSequence:
parserError("Unexpected map value indicator (expected '- ')")
of fplScalar:
parserError(
"Unexpected map value indicator (expected multiline scalar end)")
of fplSinglePairKey, fplSinglePairValue, fplDocument: debugFail()
p.lexer.skipWhitespace()
indentation = p.lexer.getColNumber(p.lexer.bufpos)
template initDocValues() {.dirty.} =
shorthands = initTable[string, string]()
anchors = initTable[string, AnchorId]()
shorthands["!"] = "!"
shorthands["!!"] = "tag:yaml.org,2002:"
nextAnchorId = 0.AnchorId
level = initLevel(fplUnknown)
tag = yTagQuestionMark
anchor = yAnchorNone
ancestry.add(FastParseLevel(kind: fplDocument, indentation: -1))
template handleTagHandle() {.dirty.} =
startToken()
if level.kind != fplUnknown: parserError("Unexpected tag handle")
if tag != yTagQuestionMark:
parserError("Only one tag handle is allowed per node")
startContent()
var
shorthandEnd: int
p.lexer.tagHandle(content, shorthandEnd)
if shorthandEnd != -1:
try:
tagUri.setLen(0)
tagUri.add(shorthands[content[0..shorthandEnd]])
tagUri.add(content[shorthandEnd + 1 .. ^1])
except KeyError:
parserError("Undefined tag shorthand: " & content[0..shorthandEnd])
try: tag = p.tagLib.tags[tagUri]
except KeyError: tag = p.tagLib.registerUri(tagUri)
else:
try: tag = p.tagLib.tags[content]
except KeyError: tag = p.tagLib.registerUri(content)
template handleAnchor() {.dirty.} =
startToken()
if level.kind != fplUnknown: parserError("Unexpected token")
if anchor != yAnchorNone:
parserError("Only one anchor is allowed per node")
startContent()
p.lexer.anchorName(content)
anchor = nextAnchorId
anchors[content] = anchor
nextAnchorId = cast[AnchorId](cast[int](nextAnchorId) + 1)
template handleAlias() {.dirty.} =
startToken()
if level.kind != fplUnknown: parserError("Unexpected token")
if anchor != yAnchorNone or tag != yTagQuestionMark:
parserError("Alias may not have anchor or tag")
startContent()
p.lexer.anchorName(content)
var id: AnchorId
try: id = anchors[content]
except KeyError: parserError("Unknown anchor")
yield aliasEvent(id)
handleObjectEnd(fpBlockAfterObject)
template leaveFlowLevel() {.dirty.} =
flowdepth.inc(-1)
if flowdepth == 0:
yieldLevelEnd()
handleObjectEnd(fpBlockAfterObject)
else:
yieldLevelEnd()
handleObjectEnd(fpFlowAfterObject)
template handlePossibleMapStart(flow: bool = false,
single: bool = false) {.dirty.} =
if level.indentation == UnknownIndentation:
var flowDepth = 0
var pos = p.lexer.bufpos
var recentJsonStyle = false
while pos < p.lexer.bufpos + 1024:
case p.lexer.buf[pos]
of ':':
if flowDepth == 0 and (p.lexer.buf[pos + 1] in spaceOrLineEnd or
recentJsonStyle):
handleObjectStart(yamlStartMap, single)
break
of lineEnd: break
of '[', '{': flowDepth.inc()
of '}', ']':
flowDepth.inc(-1)
if flowDepth < 0: break
of '?', ',':
if flowDepth == 0: break
of '#':
if p.lexer.buf[pos - 1] in space: break
of '"':
pos.inc()
while p.lexer.buf[pos] notin {'"', EndOfFile, '\l', '\c'}:
if p.lexer.buf[pos] == '\\': pos.inc()
pos.inc()
if p.lexer.buf[pos] != '"': break
of '\'':
pos.inc()
while p.lexer.buf[pos] notin {'\'', '\l', '\c', EndOfFile}:
pos.inc()
of '&', '*', '!':
if pos == p.lexer.bufpos or p.lexer.buf[p.lexer.bufpos] in space:
pos.inc()
while p.lexer.buf[pos] notin spaceOrLineEnd:
pos.inc()
continue
else: discard
if flow and p.lexer.buf[pos] notin space:
recentJsonStyle = p.lexer.buf[pos] in {']', '}', '\'', '"'}
pos.inc()
if level.indentation == UnknownIndentation: level.indentation = indentation
template handleBlockItemStart() {.dirty.} =
case level.kind
of fplUnknown: handlePossibleMapStart()
of fplSequence:
parserError("Unexpected token (expected block sequence indicator)")
of fplMapKey:
ancestry.add(level)
level = FastParseLevel(kind: fplUnknown, indentation: indentation)
of fplMapValue:
yieldEmptyScalar()
level.kind = fplMapKey
ancestry.add(level)
level = FastParseLevel(kind: fplUnknown, indentation: indentation)
of fplScalar, fplSinglePairKey, fplSinglePairValue, fplDocument: debugFail()
template handleFlowItemStart() {.dirty.} =
if level.kind == fplUnknown and ancestry[ancestry.high].kind == fplSequence:
handlePossibleMapStart(true, true)
template startToken() {.dirty.} =
p.tokenstart = p.lexer.getColNumber(p.lexer.bufpos)
template finishLine(lexer: BaseLexer) =
debug("lex: finishLine")
while lexer.buf[lexer.bufpos] notin lineEnd:
lexer.bufpos.inc()
template skipWhitespace(lexer: BaseLexer) =
debug("lex: skipWhitespace")
while lexer.buf[lexer.bufpos] in space: lexer.bufpos.inc()
template skipWhitespaceCommentsAndNewlines(lexer: BaseLexer) =
debug("lex: skipWhitespaceCommentsAndNewlines")
if lexer.buf[lexer.bufpos] != '#':
while true:
case lexer.buf[lexer.bufpos]
of space: lexer.bufpos.inc()
of '\l': lexer.bufpos = lexer.handleLF(lexer.bufpos)
of '\c': lexer.bufpos = lexer.handleCR(lexer.bufpos)
of '#': # also skip comments
lexer.bufpos.inc()
while lexer.buf[lexer.bufpos] notin lineEnd:
lexer.bufpos.inc()
else: break
template skipIndentation(lexer: BaseLexer) =
debug("lex: skipIndentation")
while lexer.buf[lexer.bufpos] == ' ': lexer.bufpos.inc()
template directiveName(lexer: BaseLexer, directive: var LexedDirective) =
debug("lex: directiveName")
directive = ldUnknown
lexer.bufpos.inc()
if lexer.buf[lexer.bufpos] == 'Y':
lexer.bufpos.inc()
if lexer.buf[lexer.bufpos] == 'A':
lexer.bufpos.inc()
if lexer.buf[lexer.bufpos] == 'M':
lexer.bufpos.inc()
if lexer.buf[lexer.bufpos] == 'L':
lexer.bufpos.inc()
if lexer.buf[lexer.bufpos] in spaceOrLineEnd:
directive = ldYaml
elif lexer.buf[lexer.bufpos] == 'T':
lexer.bufpos.inc()
if lexer.buf[lexer.bufpos] == 'A':
lexer.bufpos.inc()
if lexer.buf[lexer.bufpos] == 'G':
lexer.bufpos.inc()
if lexer.buf[lexer.bufpos] in spaceOrLineEnd:
directive = ldTag
while lexer.buf[lexer.bufpos] notin spaceOrLineEnd:
lexer.bufpos.inc()
template yamlVersion(lexer: BaseLexer, o: var string) =
debug("lex: yamlVersion")
while lexer.buf[lexer.bufpos] in space: lexer.bufpos.inc()
var c = lexer.buf[lexer.bufpos]
if c notin digits: lexerError(lexer, "Invalid YAML version number")
o.add(c)
lexer.bufpos.inc()
c = lexer.buf[lexer.bufpos]
while c in digits:
lexer.bufpos.inc()
o.add(c)
c = lexer.buf[lexer.bufpos]
if lexer.buf[lexer.bufpos] != '.':
lexerError(lexer, "Invalid YAML version number")
o.add('.')
lexer.bufpos.inc()
c = lexer.buf[lexer.bufpos]
if c notin digits: lexerError(lexer, "Invalid YAML version number")
o.add(c)
lexer.bufpos.inc()
c = lexer.buf[lexer.bufpos]
while c in digits:
o.add(c)
lexer.bufpos.inc()
c = lexer.buf[lexer.bufpos]
if lexer.buf[lexer.bufpos] notin spaceOrLineEnd:
lexerError(lexer, "Invalid YAML version number")
template lineEnding(lexer: BaseLexer) =
debug("lex: lineEnding")
if lexer.buf[lexer.bufpos] notin lineEnd:
while lexer.buf[lexer.bufpos] in space: lexer.bufpos.inc()
if lexer.buf[lexer.bufpos] in lineEnd: discard
elif lexer.buf[lexer.bufpos] == '#':
while lexer.buf[lexer.bufpos] notin lineEnd: lexer.bufpos.inc()
else:
startToken()
parserError("Unexpected token (expected comment or line end)")
template tagShorthand(lexer: BaseLexer, shorthand: var string) =
debug("lex: tagShorthand")
while lexer.buf[lexer.bufpos] in space: lexer.bufpos.inc()
assert lexer.buf[lexer.bufpos] == '!'
shorthand.add('!')
lexer.bufpos.inc()
var c = lexer.buf[lexer.bufpos]
if c in spaceOrLineEnd: discard
else:
while c != '!':
case c
of 'a' .. 'z', 'A' .. 'Z', '0' .. '9', '-':
shorthand.add(c)
lexer.bufpos.inc()
c = lexer.buf[lexer.bufpos]
else: lexerError(lexer, "Illegal character in tag shorthand")
shorthand.add(c)
lexer.bufpos.inc()
if lexer.buf[lexer.bufpos] notin spaceOrLineEnd:
lexerError(lexer, "Missing space after tag shorthand")
template tagUriMapping(lexer: BaseLexer, uri: var string) =
debug("lex: tagUriMapping")
while lexer.buf[lexer.bufpos] in space:
lexer.bufpos.inc()
var c = lexer.buf[lexer.bufpos]
if c == '!':
uri.add(c)
lexer.bufpos.inc()
c = lexer.buf[lexer.bufpos]
while c notin spaceOrLineEnd:
case c
of 'a' .. 'z', 'A' .. 'Z', '0' .. '9', '#', ';', '/', '?', ':', '@', '&',
'-', '=', '+', '$', ',', '_', '.', '~', '*', '\'', '(', ')':
uri.add(c)
lexer.bufpos.inc()
c = lexer.buf[lexer.bufpos]
else: lexerError(lexer, "Invalid tag uri")
template directivesEndMarker(lexer: var BaseLexer, success: var bool) =
debug("lex: directivesEndMarker")
success = true
for i in 0..2:
if lexer.buf[lexer.bufpos + i] != '-':
success = false
break
if success: success = lexer.buf[lexer.bufpos + 3] in spaceOrLineEnd
template documentEndMarker(lexer: var BaseLexer, success: var bool) =
debug("lex: documentEndMarker")
success = true
for i in 0..2:
if lexer.buf[lexer.bufpos + i] != '.':
success = false
break
if success: success = lexer.buf[lexer.bufpos + 3] in spaceOrLineEnd
proc unicodeSequence(lexer: var BaseLexer, length: int):
string {.raises: [YamlParserError].} =
debug("lex: unicodeSequence")
var unicodeChar = 0.int
for i in countup(0, length - 1):
lexer.bufpos.inc()
let
digitPosition = length - i - 1
c = lexer.buf[lexer.bufpos]
case c
of EndOFFile, '\l', '\c':
lexerError(lexer, "Unfinished unicode escape sequence")
of '0' .. '9':
unicodeChar = unicodechar or
(cast[int](c) - 0x30) shl (digitPosition * 4)
of 'A' .. 'F':
unicodeChar = unicodechar or
(cast[int](c) - 0x37) shl (digitPosition * 4)
of 'a' .. 'f':
unicodeChar = unicodechar or
(cast[int](c) - 0x57) shl (digitPosition * 4)
else: lexerError(lexer, "Invalid character in unicode escape sequence")
return toUTF8(cast[Rune](unicodeChar))
proc byteSequence(lexer: var BaseLexer): char {.raises: [YamlParserError].} =
debug("lex: byteSequence")
var charCode = 0.int8
for i in 0 .. 1:
lexer.bufpos.inc()
let
digitPosition = int8(1 - i)
c = lexer.buf[lexer.bufpos]
case c
of EndOfFile, '\l', 'r':
lexerError(lexer, "Unfinished octet escape sequence")
of '0' .. '9':
charCode = charCode or (int8(c) - 0x30.int8) shl (digitPosition * 4)
of 'A' .. 'F':
charCode = charCode or (int8(c) - 0x37.int8) shl (digitPosition * 4)
of 'a' .. 'f':
charCode = charCode or (int8(c) - 0x57.int8) shl (digitPosition * 4)
else: lexerError(lexer, "Invalid character in octet escape sequence")
return char(charCode)
template processQuotedWhitespace(newlines: var int) {.dirty.} =
after.setLen(0)
block outer:
while true:
case p.lexer.buf[p.lexer.bufpos]
of ' ', '\t': after.add(p.lexer.buf[p.lexer.bufpos])
of '\l':
p.lexer.bufpos = p.lexer.handleLF(p.lexer.bufpos)
break
of '\c':
p.lexer.bufpos = p.lexer.handleLF(p.lexer.bufpos)
break
else:
content.add(after)
break outer
p.lexer.bufpos.inc()
while true:
case p.lexer.buf[p.lexer.bufpos]
of ' ', '\t': discard
of '\l':
p.lexer.bufpos = p.lexer.handleLF(p.lexer.bufpos)
newlines.inc()
continue
of '\c':
p.lexer.bufpos = p.lexer.handleCR(p.lexer.bufpos)
newlines.inc()
continue
else:
if newlines == 0: discard
elif newlines == 1: content.add(' ')
else: content.addMultiple('\l', newlines - 1)
break
p.lexer.bufpos.inc()
template doubleQuotedScalar(lexer: BaseLexer, content: var string) =
debug("lex: doubleQuotedScalar")
lexer.bufpos.inc()
while true:
var c = lexer.buf[lexer.bufpos]
case c
of EndOfFile:
lexerError(lexer, "Unfinished double quoted string")
of '\\':
lexer.bufpos.inc()
case lexer.buf[lexer.bufpos]
of EndOfFile:
lexerError(lexer, "Unfinished escape sequence")
of '0': content.add('\0')
of 'a': content.add('\x07')
of 'b': content.add('\x08')
of '\t', 't': content.add('\t')
of 'n': content.add('\l')
of 'v': content.add('\v')
of 'f': content.add('\f')
of 'r': content.add('\c')
of 'e': content.add('\e')
of ' ': content.add(' ')
of '"': content.add('"')
of '/': content.add('/')
of '\\': content.add('\\')
of 'N': content.add(UTF8NextLine)
of '_': content.add(UTF8NonBreakingSpace)
of 'L': content.add(UTF8LineSeparator)
of 'P': content.add(UTF8ParagraphSeparator)
of 'x': content.add(lexer.unicodeSequence(2))
of 'u': content.add(lexer.unicodeSequence(4))
of 'U': content.add(lexer.unicodeSequence(8))
of '\l', '\c':
var newlines = 0
processQuotedWhitespace(newlines)
continue
else: lexerError(lexer, "Illegal character in escape sequence")
of '"':
lexer.bufpos.inc()
break
of '\l', '\c', '\t', ' ':
var newlines = 1
processQuotedWhitespace(newlines)
continue
else:
content.add(c)
lexer.bufpos.inc()
template singleQuotedScalar(lexer: BaseLexer, content: var string) =
debug("lex: singleQuotedScalar")
lexer.bufpos.inc()
while true:
case lexer.buf[lexer.bufpos]
of '\'':
lexer.bufpos.inc()
if lexer.buf[lexer.bufpos] == '\'': content.add('\'')
else: break
of EndOfFile: lexerError(lexer, "Unfinished single quoted string")
of '\l', '\c', '\t', ' ':
var newlines = 1
processQuotedWhitespace(newlines)
continue
else: content.add(lexer.buf[lexer.bufpos])
lexer.bufpos.inc()
proc isPlainSafe(lexer: BaseLexer, index: int, context: YamlContext): bool =
case lexer.buf[lexer.bufpos + 1]
of spaceOrLineEnd: result = false
of flowIndicators: result = context == cBlock
else: result = true
# tried this for performance optimization, but it didn't optimize any
# performance. keeping it around for future reference.
#const
# plainCharOut = {'!', '\"', '$'..'9', ';'..'\xFF'}
# plainCharIn = {'!', '\"', '$'..'+', '-'..'9', ';'..'Z', '\\', '^'..'z',
# '|', '~'..'\xFF'}
#template isPlainChar(c: char, context: YamlContext): bool =
# when context == cBlock: c in plainCharOut
# else: c in plainCharIn
template plainScalar(lexer: BaseLexer, content: var string,
context: YamlContext) =
debug("lex: plainScalar")
content.add(lexer.buf[lexer.bufpos])
block outer:
while true:
lexer.bufpos.inc()
let c = lexer.buf[lexer.bufpos]
case c
of ' ', '\t':
after.setLen(1)
after[0] = c
while true:
lexer.bufpos.inc()
let c2 = lexer.buf[lexer.bufpos]
case c2
of ' ', '\t': after.add(c2)
of lineEnd: break outer
of ':':
if lexer.isPlainSafe(lexer.bufpos + 1, context):
content.add(after & ':')
break
else: break outer
of '#': break outer
of flowIndicators:
if context == cBlock:
content.add(after)
content.add(c2)
break
else: break outer
else:
content.add(after)
content.add(c2)
break
of flowIndicators:
when context == cFlow: break
else: content.add(c)
of lineEnd: break
of ':':
if lexer.isPlainSafe(lexer.bufpos + 1, context): content.add(':')
else: break outer
else: content.add(c)
debug("lex: \"" & content & '\"')
template continueMultilineScalar() {.dirty.} =
content.add(if newlines == 1: " " else: repeat('\l', newlines - 1))
startToken()
p.lexer.plainScalar(content, cBlock)
state = fpBlockAfterPlainScalar
template handleFlowPlainScalar() {.dirty.} =
startContent()
startToken()
p.lexer.plainScalar(content, cFlow)
if p.lexer.buf[p.lexer.bufpos] in {'{', '}', '[', ']', ',', ':', '#'}:
discard
else:
newlines = 0
while true:
case p.lexer.buf[p.lexer.bufpos]
of ':':
if p.lexer.isPlainSafe(p.lexer.bufpos + 1, cFlow):
if newlines == 1:
content.add(' ')
newlines = 0
elif newlines > 1:
content.addMultiple(' ', newlines - 1)
newlines = 0
p.lexer.plainScalar(content, cFlow)
break
of '#', EndOfFile: break
of '\l':
p.lexer.bufpos = p.lexer.handleLF(p.lexer.bufpos)
newlines.inc()
of '\c':
p.lexer.bufpos = p.lexer.handleCR(p.lexer.bufpos)
newlines.inc()
of flowIndicators: break
of ' ', '\t': p.lexer.skipWhitespace()
else:
if newlines == 1:
content.add(' ')
newlines = 0
elif newlines > 1:
content.addMultiple(' ', newlines - 1)
newlines = 0
p.lexer.plainScalar(content, cFlow)
yieldShallowScalar(content)
handleObjectEnd(fpFlowAfterObject)
template tagHandle(lexer: var BaseLexer, content: var string,
shorthandEnd: var int) =
debug("lex: tagHandle")
shorthandEnd = 0
content.add(lexer.buf[lexer.bufpos])
var i = 0
while true:
lexer.bufpos.inc()
i.inc()
let c = lexer.buf[lexer.bufpos]
case c
of spaceOrLineEnd:
if shorthandEnd == -1: lexerError(lexer, "Unclosed verbatim tag")
break
of '!':
if shorthandEnd == -1 and i == 2:
content.add(c)
continue
elif shorthandEnd != 0:
lexerError(lexer, "Illegal character in tag suffix")
shorthandEnd = i
content.add(c)
of 'a' .. 'z', 'A' .. 'Z', '0' .. '9', '#', ';', '/', '?', ':', '@', '&',
'-', '=', '+', '$', '_', '.', '~', '*', '\'', '(', ')':
content.add(c)
of ',':
if shortHandEnd > 0: break # ',' after shorthand is flow indicator
content.add(c)
of '<':
if i == 1:
shorthandEnd = -1
startContent()
else: lexerError(lexer, "Illegal character in tag handle")
of '>':
if shorthandEnd == -1:
lexer.bufpos.inc()
if lexer.buf[lexer.bufpos] notin spaceOrLineEnd:
lexerError(lexer, "Missing space after verbatim tag handle")
break
else: lexerError(lexer, "Illegal character in tag handle")
of '%':
if shorthandEnd != 0: content.add(lexer.byteSequence())
else: lexerError(lexer, "Illegal character in tag handle")
else: lexerError(lexer, "Illegal character in tag handle")
template anchorName(lexer: BaseLexer, content: var string) =
debug("lex: anchorName")
while true:
lexer.bufpos.inc()
let c = lexer.buf[lexer.bufpos]
case c
of spaceOrLineEnd, '[', ']', '{', '}', ',': break
else: content.add(c)
template consumeLineIfEmpty(lex: BaseLexer): bool =
var result = true
while true:
lex.bufpos.inc()
case lex.buf[lex.bufpos]
of ' ', '\t': discard
of '\l':
lex.bufpos = lex.handleLF(lex.bufpos)
break
of '\c':
lex.bufpos = lex.handleCR(lex.bufpos)
break
of '#', EndOfFile:
lex.lineEnding()
handleLineEnd(false)
break
else:
result = false
break
result
template startScalar(t: ScalarType) {.dirty.} =
newlines = 0
level.kind = fplScalar
scalarType = t
template blockScalarHeader() {.dirty.} =
debug("lex: blockScalarHeader")
chomp = ctClip
level.indentation = UnknownIndentation
if tag == yTagQuestionMark: tag = yTagExclamationMark
let t = if p.lexer.buf[p.lexer.bufpos] == '|': stLiteral else: stFolded
while true:
p.lexer.bufpos.inc()
case p.lexer.buf[p.lexer.bufpos]
of '+':
if chomp != ctClip:
lexerError(p.lexer, "Only one chomping indicator is allowed")
chomp = ctKeep
of '-':
if chomp != ctClip:
lexerError(p.lexer, "Only one chomping indicator is allowed")
chomp = ctStrip
of '1'..'9':
if level.indentation != UnknownIndentation:
lexerError(p.lexer, "Only one indentation indicator is allowed")
level.indentation = ancestry[ancestry.high].indentation +
ord(p.lexer.buf[p.lexer.bufpos]) - ord('\x30')
of spaceOrLineEnd: break
else: lexerError(p.lexer, "Illegal character in block scalar header: '" &
p.lexer.buf[p.lexer.bufpos] & "'")
recentWasMoreIndented = false
p.lexer.lineEnding()
handleLineEnd(true)
startScalar(t)
startContent()
template blockScalarLine() {.dirty.} =
debug("lex: blockScalarLine")
if indentation < level.indentation:
if p.lexer.buf[p.lexer.bufpos] == '#':
# skip all following comment lines
while indentation > ancestry[ancestry.high].indentation:
p.lexer.lineEnding()
handleLineEnd(true)
newlines.inc(-1)
p.lexer.skipIndentation()
indentation = p.lexer.getColNumber(p.lexer.bufpos)
if indentation > ancestry[ancestry.high].indentation:
p.lexer.lexerError("Invalid content in block scalar after comments")
closeMoreIndentedLevels()
else:
p.lexer.lexerError(
"Invalid indentation (expected indentation of at least " &
$level.indentation & " spaces)")
else:
if level.indentation == UnknownIndentation:
if p.lexer.buf[p.lexer.bufpos] in lineEnd:
handleLineEnd(true)
continue
else:
level.indentation = indentation
content.addMultiple('\l', newlines)
elif indentation > level.indentation or p.lexer.buf[p.lexer.bufpos] == '\t':
content.addMultiple('\l', newlines)
recentWasMoreIndented = true
content.addMultiple(' ', indentation - level.indentation)
elif scalarType == stFolded:
if recentWasMoreIndented:
recentWasMoreIndented = false
newlines.inc()
if newlines == 0: discard
elif newlines == 1: content.add(' ')
else: content.addMultiple('\l', newlines - 1)
else: content.addMultiple('\l', newlines)
newlines = 0
while p.lexer.buf[p.lexer.bufpos] notin lineEnd:
content.add(p.lexer.buf[p.lexer.bufpos])
p.lexer.bufpos.inc()
handleLineEnd(true)
proc parse*(p: YamlParser, s: Stream): YamlStream =
var backend = iterator(): YamlStreamEvent =
var
state = fpInitial
shorthands: Table[string, string]
anchors: Table[string, AnchorId]
nextAnchorId: AnchorId
content: string = ""
after: string = ""
tagUri: string = ""
tag: TagId
anchor: AnchorId
ancestry = newSeq[FastParseLevel]()
level: FastParseLevel
indentation: int
newlines: int
flowdepth: int = 0
explicitFlowKey: bool
scalarType: ScalarType
recentWasMoreIndented: bool
chomp: ChompType
p.lexer.open(s)
initDocValues()
while true:
case state
of fpInitial:
debug("state: initial")
case p.lexer.buf[p.lexer.bufpos]
of '%':
var ld: LexedDirective
startToken()
p.lexer.directiveName(ld)
case ld
of ldYaml:
var version = ""
startToken()
p.lexer.yamlVersion(version)
if version != "1.2":
if p.callback != nil:
p.callback(p.lexer.lineNumber, p.getColNumber(),
p.getLineContent(),
"Version is not 1.2, but " & version)
discard
p.lexer.lineEnding()
handleLineEnd(false)
of ldTag:
var shorthand = ""
tagUri.setLen(0)
startToken()
p.lexer.tagShorthand(shorthand)
p.lexer.tagUriMapping(tagUri)
shorthands[shorthand] = tagUri
p.lexer.lineEnding()
handleLineEnd(false)
of ldUnknown:
if p.callback != nil:
p.callback(p.lexer.lineNumber, p.getColNumber(),
p.getLineContent(), "Unknown directive")
p.lexer.finishLine()
handleLineEnd(false)
of ' ', '\t':
if not p.lexer.consumeLineIfEmpty():
indentation = p.lexer.getColNumber(p.lexer.bufpos)
yield startDocEvent()
state = fpBlockObjectStart
of '\l': p.lexer.bufpos = p.lexer.handleLF(p.lexer.bufpos)
of '\c': p.lexer.bufpos = p.lexer.handleCR(p.lexer.bufpos)
of EndOfFile: return
of '#':
p.lexer.lineEnding()
handleLineEnd(false)
of '-':
var success: bool
startToken()
p.lexer.directivesEndMarker(success)
yield startDocEvent()
if success:
p.lexer.bufpos.inc(3)
state = fpBlockObjectStart
else:
yield startDocEvent()
state = fpBlockObjectStart
of fpBlockAfterPlainScalar:
debug("state: blockAfterPlainScalar")
p.lexer.skipWhitespace()
case p.lexer.buf[p.lexer.bufpos]
of '\l':
if level.kind notin {fplUnknown, fplScalar}:
startToken()
parserError("Unexpected scalar")
startScalar(stFlow)
p.lexer.bufpos = p.lexer.handleLF(p.lexer.bufpos)
newlines.inc()
state = fpBlockObjectStart
of '\c':
if level.kind notin {fplUnknown, fplScalar}:
startToken()
parserError("Unexpected scalar")
startScalar(stFlow)
p.lexer.bufpos = p.lexer.handleCR(p.lexer.bufpos)
newlines.inc()
state = fpBlockObjectStart
else:
yieldShallowScalar(content)
handleObjectEnd(fpBlockAfterObject)
of fpBlockAfterObject:
debug("state: blockAfterObject")
p.lexer.skipWhitespace()
case p.lexer.buf[p.lexer.bufpos]
of EndOfFile:
closeEverything()
break
of '\l':
state = fpBlockObjectStart
p.lexer.bufpos = p.lexer.handleLF(p.lexer.bufpos)
of '\c':
state = fpBlockObjectStart
p.lexer.bufpos = p.lexer.handleCR(p.lexer.bufpos)
of ':':
case level.kind
of fplUnknown:
handleObjectStart(yamlStartMap)
of fplMapKey:
yield scalarEvent("", yTagQuestionMark, yAnchorNone)
level.kind = fplMapValue
ancestry.add(level)
level = initLevel(fplUnknown)
of fplMapValue:
level.kind = fplMapValue
ancestry.add(level)
level = initLevel(fplUnknown)
of fplSequence:
startToken()
parserError("Illegal token (expected sequence item)")
of fplScalar:
startToken()
parserError("Multiline scalars may not be implicit map keys")
of fplSinglePairKey, fplSinglePairValue, fplDocument: debugFail()
p.lexer.bufpos.inc()
p.lexer.skipWhitespace()
indentation = p.lexer.getColNumber(p.lexer.bufpos)
state = fpBlockObjectStart
of '#':
p.lexer.lineEnding()
handleLineEnd(true)
state = fpBlockObjectStart
else:
startToken()
parserError("Illegal token (expected ':', comment or line end)")
of fpBlockObjectStart:
debug("state: blockObjectStart")
p.lexer.skipIndentation()
indentation = p.lexer.getColNumber(p.lexer.bufpos)
if indentation == 0:
var success: bool
p.lexer.directivesEndMarker(success)
if success:
p.lexer.bufpos.inc(3)
closeEverything()
initDocValues()
yield startDocEvent()
continue
p.lexer.documentEndMarker(success)
if success:
closeEverything()
p.lexer.bufpos.inc(3)
p.lexer.lineEnding()
handleLineEnd(false)
state = fpAfterDocument
continue
if indentation <= ancestry[ancestry.high].indentation:
if p.lexer.buf[p.lexer.bufpos] in lineEnd:
handleLineEnd(true)
continue
elif p.lexer.buf[p.lexer.bufpos] == '#':
p.lexer.lineEnding()
handleLineEnd(true)
continue
elif p.lexer.buf[p.lexer.bufpos] == '-' and not
p.lexer.isPlainSafe(p.lexer.bufpos + 1, cBlock):
closeMoreIndentedLevels(true)
else: closeMoreIndentedLevels()
elif indentation <= level.indentation and
p.lexer.buf[p.lexer.bufpos] in lineEnd:
handleLineEnd(true)
continue
if level.kind == fplScalar and scalarType != stFlow:
blockScalarLine()
continue
case p.lexer.buf[p.lexer.bufpos]
of '\l':
p.lexer.bufpos = p.lexer.handleLF(p.lexer.bufpos)
newlines.inc()
if level.kind == fplUnknown: level.indentation = UnknownIndentation
of '\c':
p.lexer.bufpos = p.lexer.handleCR(p.lexer.bufpos)
newlines.inc()
if level.kind == fplUnknown: level.indentation = UnknownIndentation
of EndOfFile:
closeEverything()
return
of '#':
p.lexer.lineEnding()
handleLineEnd(true)
if level.kind == fplUnknown: level.indentation = UnknownIndentation
of '\'':
handleBlockItemStart()
startContent()
startToken()
p.lexer.singleQuotedScalar(content)
if tag == yTagQuestionMark: tag = yTagExclamationMark
yieldShallowScalar(content)
handleObjectEnd(fpBlockAfterObject)
of '"':
handleBlockItemStart()
startContent()
startToken()
p.lexer.doubleQuotedScalar(content)
if tag == yTagQuestionMark: tag = yTagExclamationMark
yieldShallowScalar(content)
handleObjectEnd(fpBlockAfterObject)
of '|', '>':
blockScalarHeader()
continue
of '-':
if p.lexer.isPlainSafe(p.lexer.bufpos + 1, cBlock):
if level.kind == fplScalar: continueMultilineScalar()
else:
handleBlockItemStart()
startContent()
startToken()
p.lexer.plainScalar(content, cBlock)
state = fpBlockAfterPlainScalar
else:
p.lexer.bufpos.inc()
handleBlockSequenceIndicator()
of '!':
handleBlockItemStart()
handleTagHandle()
of '&':
handleBlockItemStart()
handleAnchor()
of '*':
handleBlockItemStart()
handleAlias()
of '[', '{':
handleBlockItemStart()
state = fpFlow
of '?':
if p.lexer.isPlainSafe(p.lexer.bufpos + 1, cBlock):
if level.kind == fplScalar: continueMultilineScalar()
else:
handleBlockItemStart()
startContent()
startToken()
p.lexer.plainScalar(content, cBlock)
state = fpBlockAfterPlainScalar
else:
p.lexer.bufpos.inc()
handleMapKeyIndicator()
of ':':
if p.lexer.isPlainSafe(p.lexer.bufpos + 1, cBlock):
if level.kind == fplScalar: continueMultilineScalar()
else:
handleBlockItemStart()
startContent()
startToken()
p.lexer.plainScalar(content, cBlock)
state = fpBlockAfterPlainScalar
else:
p.lexer.bufpos.inc()
handleMapValueIndicator()
of '@', '`':
lexerError(p.lexer, "Reserved characters cannot start a plain scalar")
of '\t':
if level.kind == fplScalar:
p.lexer.skipWhitespace()
continueMultilineScalar()
else: lexerError(p.lexer, "\\t cannot start any token")
else:
if level.kind == fplScalar: continueMultilineScalar()
else:
handleBlockItemStart()
startContent()
startToken()
p.lexer.plainScalar(content, cBlock)
state = fpBlockAfterPlainScalar
of fpExpectDocEnd:
debug("state: expectDocEnd")
case p.lexer.buf[p.lexer.bufpos]
of '-':
var success: bool
p.lexer.directivesEndMarker(success)
if success:
p.lexer.bufpos.inc(3)
yield endDocEvent()
discard ancestry.pop()
initDocValues()
yield startDocEvent()
state = fpBlockObjectStart
else: parserError("Unexpected content (expected document end)")
of '.':
var isDocumentEnd: bool
startToken()
p.lexer.documentEndMarker(isDocumentEnd)
if isDocumentEnd:
closeEverything()
p.lexer.bufpos.inc(3)
p.lexer.lineEnding()
handleLineEnd(false)
state = fpAfterDocument
else: parserError("Unexpected content (expected document end)")
of ' ', '\t', '#':
p.lexer.lineEnding()
handleLineEnd(true)
of '\l': p.lexer.bufpos = p.lexer.handleLF(p.lexer.bufpos)
of '\c': p.lexer.bufpos = p.lexer.handleCR(p.lexer.bufpos)
of EndOfFile:
yield endDocEvent()
break
else:
startToken()
parserError("Unexpected content (expected document end)")
of fpAfterDocument:
debug("state: afterDocument")
case p.lexer.buf[p.lexer.bufpos]
of '.':
var isDocumentEnd: bool
startToken()
p.lexer.documentEndMarker(isDocumentEnd)
if isDocumentEnd:
p.lexer.bufpos.inc(3)
p.lexer.lineEnding()
handleLineEnd(false)
else:
initDocValues()
yield startDocEvent()
state = fpBlockObjectStart
of '#':
p.lexer.lineEnding()
handleLineEnd(false)
of '\t', ' ':
if not p.lexer.consumeLineIfEmpty():
indentation = p.lexer.getColNumber(p.lexer.bufpos)
initDocValues()
yield startDocEvent()
state = fpBlockObjectStart
of EndOfFile: break
else:
initDocValues()
state = fpInitial
of fpFlow:
debug("state: flow")
p.lexer.skipWhitespaceCommentsAndNewlines()
case p.lexer.buf[p.lexer.bufpos]
of '{':
handleFlowItemStart()
handleObjectStart(yamlStartMap)
flowdepth.inc()
p.lexer.bufpos.inc()
explicitFlowKey = false
of '[':
handleFlowItemStart()
handleObjectStart(yamlStartSeq)
flowdepth.inc()
p.lexer.bufpos.inc()
of '}':
assert(level.kind == fplUnknown)
level = ancestry.pop()
case level.kind
of fplMapValue:
yieldEmptyScalar()
level.kind = fplMapKey
of fplMapKey:
if tag != yTagQuestionMark or anchor != yAnchorNone or
explicitFlowKey:
yieldEmptyScalar()
yield scalarEvent("", yTagQuestionMark, yAnchorNone)
of fplSequence:
startToken()
parserError("Unexpected token (expected ']')")
of fplSinglePairValue:
startToken()
parserError("Unexpected token (expected ']')")
of fplUnknown, fplScalar, fplSinglePairKey, fplDocument: debugFail()
p.lexer.bufpos.inc()
leaveFlowLevel()
of ']':
assert(level.kind == fplUnknown)
level = ancestry.pop()
case level.kind
of fplSequence:
if tag != yTagQuestionMark or anchor != yAnchorNone:
yieldEmptyScalar()
of fplSinglePairValue:
yieldEmptyScalar()
level = ancestry.pop()
yield endMapEvent()
assert(level.kind == fplSequence)
of fplMapKey, fplMapValue:
startToken()
parserError("Unexpected token (expected '}')")
of fplUnknown, fplScalar, fplSinglePairKey, fplDocument: debugFail()
p.lexer.bufpos.inc()
leaveFlowLevel()
of ',':
assert(level.kind == fplUnknown)
level = ancestry.pop()
case level.kind
of fplSequence: yieldEmptyScalar()
of fplMapValue:
yieldEmptyScalar()
level.kind = fplMapKey
explicitFlowKey = false
of fplMapKey:
yieldEmptyScalar
yield scalarEvent("", yTagQuestionMark, yAnchorNone)
explicitFlowKey = false
of fplSinglePairValue:
yieldEmptyScalar()
level = ancestry.pop()
yield endMapEvent()
assert(level.kind == fplSequence)
of fplUnknown, fplScalar, fplSinglePairKey, fplDocument: debugFail()
ancestry.add(level)
level = initLevel(fplUnknown)
p.lexer.bufpos.inc()
of ':':
if p.lexer.isPlainSafe(p.lexer.bufpos + 1, cFlow):
handleFlowItemStart()
handleFlowPlainScalar()
else:
level = ancestry.pop()
case level.kind
of fplSequence:
yield startMapEvent(tag, anchor)
debug("started single-pair map at " &
(if level.indentation == UnknownIndentation:
$indentation else: $level.indentation))
tag = yTagQuestionMark
anchor = yAnchorNone
if level.indentation == UnknownIndentation:
level.indentation = indentation
ancestry.add(level)
level = initLevel(fplSinglePairValue)
yield scalarEvent("")
of fplMapValue, fplSinglePairValue:
startToken()
parserError("Unexpected token (expected ',')")
of fplMapKey:
yieldEmptyScalar()
level.kind = fplMapValue
of fplSinglePairKey:
yieldEmptyScalar()
level.kind = fplSinglePairValue
of fplUnknown, fplScalar, fplDocument: debugFail()
ancestry.add(level)
level = initLevel(fplUnknown)
p.lexer.bufpos.inc()
of '\'':
handleFlowItemStart()
startContent()
startToken()
p.lexer.singleQuotedScalar(content)
if tag == yTagQuestionMark: tag = yTagExclamationMark
yieldShallowScalar(content)
handleObjectEnd(fpFlowAfterObject)
of '"':
handleFlowItemStart()
startContent()
startToken()
p.lexer.doubleQuotedScalar(content)
if tag == yTagQuestionMark: tag = yTagExclamationMark
yieldShallowScalar(content)
handleObjectEnd(fpFlowAfterObject)
of '!':
handleFlowItemStart()
handleTagHandle()
of '&':
handleFlowItemStart()
handleAnchor()
of '*':
handleAlias()
state = fpFlowAfterObject
of '?':
if p.lexer.isPlainSafe(p.lexer.bufpos + 1, cFlow):
handleFlowItemStart()
handleFlowPlainScalar()
elif explicitFlowKey:
startToken()
parserError("Duplicate '?' in flow mapping")
elif level.kind == fplUnknown:
case ancestry[ancestry.high].kind
of fplMapKey, fplMapValue, fplDocument: discard
of fplSequence: handleObjectStart(yamlStartMap, true)
else:
startToken()
parserError("Unexpected token")
explicitFlowKey = true
p.lexer.bufpos.inc()
else:
explicitFlowKey = true
p.lexer.bufpos.inc()
else:
handleFlowItemStart()
handleFlowPlainScalar()
of fpFlowAfterObject:
debug("state: flowAfterObject")
p.lexer.skipWhitespaceCommentsAndNewlines()
case p.lexer.buf[p.lexer.bufpos]
of ']':
case level.kind
of fplSequence: discard
of fplMapKey, fplMapValue:
startToken()
parserError("Unexpected token (expected '}')")
of fplSinglePairValue:
level = ancestry.pop()
assert(level.kind == fplSequence)
yield endMapEvent()
of fplScalar, fplUnknown, fplSinglePairKey, fplDocument: debugFail()
p.lexer.bufpos.inc()
leaveFlowLevel()
of '}':
case level.kind
of fplMapKey, fplMapValue: discard
of fplSequence, fplSinglePairValue:
startToken()
parserError("Unexpected token (expected ']')")
of fplUnknown, fplScalar, fplSinglePairKey, fplDocument: debugFail()
p.lexer.bufpos.inc()
leaveFlowLevel()
of ',':
case level.kind
of fplSequence: discard
of fplMapValue:
yield scalarEvent("", yTagQuestionMark, yAnchorNone)
level.kind = fplMapKey
explicitFlowKey = false
of fplSinglePairValue:
level = ancestry.pop()
assert(level.kind == fplSequence)
yield endMapEvent()
of fplMapKey: explicitFlowKey = false
of fplUnknown, fplScalar, fplSinglePairKey, fplDocument: debugFail()
ancestry.add(level)
level = initLevel(fplUnknown)
state = fpFlow
p.lexer.bufpos.inc()
of ':':
case level.kind
of fplSequence, fplMapKey:
startToken()
parserError("Unexpected token (expected ',')")
of fplMapValue, fplSinglePairValue: discard
of fplUnknown, fplScalar, fplSinglePairKey, fplDocument: debugFail()
ancestry.add(level)
level = initLevel(fplUnknown)
state = fpFlow
p.lexer.bufpos.inc()
of '#':
p.lexer.lineEnding()
handleLineEnd(true)
of EndOfFile:
startToken()
parserError("Unclosed flow content")
else:
startToken()
parserError("Unexpected content (expected flow indicator)")
try: result = initYamlStream(backend)
except Exception: debugFail() # compiler error