ybase

type Adjacency struct {
	Linum  int
	Column int
	Focus  rune
	String string
	Line   string
}

type Bytes []byte

type Context struct {
	Target *ContextLine
	Lines  []*ContextLine
}

type ContextLine struct {
	Linum int
	Line  []byte
}

type DebugFunc func(msg string, v ...any)

type Lexer interface {
	Scanner
	// DoLex runs the lexical analysis.
	// Returns EOF if EOF or an error occurs.
	DoLex(callback func(Token)) int
}

type Pos interface {
	Line() int
	Column() int
	Offset() int
	Add(r rune) Pos
}

type Reader interface {
	// ResetBuffer clears the buffer.
	ResetBuffer()
	// Buffer returns the read runes.
	Buffer() string
	// Next gets the next rune and advances the pos.
	Next() rune
	// Peek gets the next rune but keeps the pos.
	Peek() rune
	// Discard ignores the next rune.
	Discard() rune
	// Err returns an error during the reading.
	Err() error
	// Debugf outputs debug logs.
	Debugf(msg string, v ...any)
	// Errorf outputs logs and set an error.
	Errorf(err error, msg string, v ...any)
	// DiscardWhile calls Discard() while pred(Peek()).
	DiscardWhile(pred func(rune) bool)
	// NextWhile calls Next() while pred(Peek()).
	NextWhile(pred func(rune) bool)
	// Pos returns the current position.
	Pos() Pos
}

type ScanFunc func(Reader) int

type Scanner interface {
	Reader
	Scan() int
	// Error consumes an error from yyLexer.
	Error(msg string)
}

type Token interface {
	Type() int
	Value() string
	Start() Pos
	End() Pos
}