lexer

Documentation

Index

• Constants
• Variables
• type ActionRow
  • func (a ActionRow) String() string
• type ActionTable
• type Lexer
  • func NewLexer(src []byte) *Lexer
  • func NewLexerFile(fpath string) (*Lexer, error)
  • func (l *Lexer) Reset()
  • func (l *Lexer) Scan() (tok *token.Token)
• type SourceContext
  • func (s *SourceContext) Source() string
• type TransitionTable

Constants

const (
	NoState    = -1
	NumStates  = 4
	NumSymbols = 4
)

Variables

var ActTab = ActionTable{
	ActionRow{
		Accept: 0,
		Ignore: "",
	},
	ActionRow{
		Accept: -1,
		Ignore: "!whitespace",
	},
	ActionRow{
		Accept: 4,
		Ignore: "",
	},
	ActionRow{
		Accept: 2,
		Ignore: "",
	},
}

var TransTab = TransitionTable{

	func(r rune) int {
		switch {
		case r == 32:
			return 1
		case r == 98:
			return 2
		case r == 99:
			return 3
		}
		return NoState
	},

	func(r rune) int {
		switch {
		}
		return NoState
	},

	func(r rune) int {
		switch {
		}
		return NoState
	},

	func(r rune) int {
		switch {
		}
		return NoState
	},
}

Types

type ActionRow

type ActionRow struct {
	Accept token.Type
	Ignore string
}

func (ActionRow) String

func (a ActionRow) String() string

type ActionTable

type ActionTable [NumStates]ActionRow

type Lexer

type Lexer struct {
	Context token.Context
	// contains filtered or unexported fields
}

func NewLexer

func NewLexer(src []byte) *Lexer

func NewLexerFile

func NewLexerFile(fpath string) (*Lexer, error)

func (*Lexer) Reset

func (l *Lexer) Reset()

func (*Lexer) Scan

func (l *Lexer) Scan() (tok *token.Token)

type SourceContext

type SourceContext struct {
	Filepath string
}

SourceContext is a simple instance of a token.Context which contains the name of the source file.

func (*SourceContext) Source

func (s *SourceContext) Source() string

type TransitionTable

type TransitionTable [NumStates]func(rune) int

Let s be the current state Let r be the current input rune transitionTable[s](r) returns the next state.