Assoc = enum
  assocLeft, assocRight

CapFrame[S] = object
  cft*: CapFrameType
  name*: string
  si*: int
  ck*: CapKind
  when S is char:
    sPushed*: string
  else:
    sPushed*: S

CapFrameType = enum
  cftOpen, cftClose

CapKind = enum
  ckVal, ckPushed, ckCodeBlock, ckRef

CharSet = set[char]

Grammar = ref object
  rules*: Table[string, Rule]
  templates*: Table[string, Template]

Inst = object
  case op*: Opcode
  of opChoice, opCommit:
    ipOffset*: int
    siOffset*: int
  of opChr:
    ch*: char
  of opLit:
    lit*: NimNode
  of opCall, opJump:
    callLabel*: string
    callOffset*: int
  of opSet, opSpan:
    cs*: CharSet
  of opCapOpen, opCapClose:
    capKind*: CapKind
    capAction*: NimNode
    capName*: string
    capSiOffset*: int
  of opErr:
    msg*: string
  of opFail, opReturn, opAny, opNop, opPrecPop:
    nil
  of opBackref:
    refName*: string
  of opPrecPush:
    prec*: int
    assoc*: Assoc
  failOffset*: int
  name*: string
  nimNode*: NimNode
  indent*: int

NPegCaptureOutOfRangeError = object of NPegException

NPegException = object of CatchableError
  matchLen*: int
  matchMax*: int

NPegParseError = object of NPegException

NPegStackOverflowError = object of NPegException

NPegUnknownBackrefError = object of NPegException

Opcode = enum
  opChr, opLit, opSet, opAny, opNop, opSpan, opChoice, opCommit, opCall, opJump,
  opReturn, opFail, opCapOpen, opCapClose, opBackref, opErr, opPrecPush,
  opPrecPop

Patt = seq[Inst]

Program = object
  patt*: Patt
  symTab*: SymTab

Ref = object
  key*: string
  val*: string

Rule = object
  name*: string
  patt*: Patt
  repr*: string
  lineInfo*: LineInfo

Symbol = object
  ip*: int
  name*: string
  repr*: string
  lineInfo*: LineInfo

SymTab = object
  syms*: seq[Symbol]

Template = ref object
  name*: string
  args*: seq[string]
  code*: NimNode

npegBackStackSize {.intdefine.} = 1024

npegDebug = false

npegExpand = false

npegGcsafe = false

npegGraph = false

npegInlineMaxLen {.intdefine.} = 30

npegOptCapShift = true

npegOptChoiceCommit = true

npegOptHeadFail = true

npegOptimize {.intdefine.} = 255

npegOptSets = true

npegPattMaxLen {.intdefine.} = 4096

npegRetStackSize {.intdefine.} = 1024

npegStacktrace = false

npegTrace = false