cmd/evm: move compiler to evm

cmd/easm/examples/auto_push.asm

@@ -1 +0,0 @@
-	push 256

cmd/easm/examples/jump.asm

@@ -1,8 +0,0 @@
-jump @main
-	push 1
-other:
-	push 0
-	push 0
-	mstore
-main:
-	push 1

cmd/easm/examples/large_string.asm

@@ -1,2 +0,0 @@
-	push "hellooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo"
-

cmd/easm/examples/prog.asm

@@ -1,17 +0,0 @@
-	jump @main
-my_label:
-	push 0
-	push 1
-	mstore
-
-	push 0
-	push 5
-	push 10
-	log1
-	stop
-main:
-	push 1
-	push 1
-	eq
-
-	jumpi @my_label

cmd/easm/examples/push.asm

@@ -1,3 +0,0 @@
-push 1
-push 2
-add

cmd/easm/examples/string.asm

@@ -1,3 +0,0 @@
-	push "hello"
-	push 0
-	mstore

cmd/easm/lex_test.go

@@ -1,20 +0,0 @@
-package main
-
-import "testing"
-
-func lexAll(src string) []item {
-	ch := lex("test.asm", []byte(src), false)
-
-	var tokens []item
-	for i := range ch {
-		tokens = append(tokens, i)
-	}
-	return tokens
-}
-
-func TestComment(t *testing.T) {
-	tokens := lexAll(";; this is a comment")
-	if len(tokens) != 2 { // {new line, EOF}
-		t.Error("expected no tokens")
-	}
-}

cmd/evm/compiler.go

@@ -0,0 +1,55 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of go-ethereum.
+//
+// go-ethereum is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// go-ethereum is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.
+
+package main
+
+import (
+	"errors"
+	"fmt"
+	"io/ioutil"
+
+	"github.com/ethereum/go-ethereum/cmd/evm/internal/compiler"
+
+	cli "gopkg.in/urfave/cli.v1"
+)
+
+var compileCommand = cli.Command{
+	Action:    compileCmd,
+	Name:      "compile",
+	Usage:     "compiles easm source to evm binary",
+	ArgsUsage: "<file>",
+}
+
+func compileCmd(ctx *cli.Context) error {
+	debug := ctx.GlobalBool(DebugFlag.Name)
+
+	if len(ctx.Args().First()) == 0 {
+		return errors.New("filename required")
+	}
+
+	fn := ctx.Args().First()
+	src, err := ioutil.ReadFile(fn)
+	if err != nil {
+		return err
+	}
+
+	bin, err := compiler.Compile(fn, src, debug)
+	if err != nil {
+		return err
+	}
+	fmt.Println(bin)
+	return nil
+}

cmd/evm/internal/compiler/compiler.go

@@ -0,0 +1,39 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of go-ethereum.
+//
+// go-ethereum is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// go-ethereum is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.
+
+package compiler
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/ethereum/go-ethereum/core/asm"
+)
+
+func Compile(fn string, src []byte, debug bool) (string, error) {
+	compiler := asm.NewCompiler(debug)
+	compiler.Feed(asm.Lex(fn, src, debug))
+
+	bin, compileErrors := compiler.Compile()
+	if len(compileErrors) > 0 {
+		// report errors
+		for _, err := range compileErrors {
+			fmt.Printf("%s:%v\n", fn, err)
+		}
+		return "", errors.New("compiling failed")
+	}
+	return bin, nil
+}

cmd/evm/main.go

@@ -18,21 +18,11 @@
 package main
 
 import (
-	"bytes"
 	"fmt"
-	"io/ioutil"
 	"math/big"
 	"os"
-	goruntime "runtime"
-	"time"
 
 	"github.com/ethereum/go-ethereum/cmd/utils"
-	"github.com/ethereum/go-ethereum/common"
-	"github.com/ethereum/go-ethereum/core/state"
-	"github.com/ethereum/go-ethereum/core/vm"
-	"github.com/ethereum/go-ethereum/core/vm/runtime"
-	"github.com/ethereum/go-ethereum/ethdb"
-	"github.com/ethereum/go-ethereum/log"
 	"gopkg.in/urfave/cli.v1"
 )
 
@@ -109,113 +99,10 @@ func init() {
 		InputFlag,
 		DisableGasMeteringFlag,
 	}
-	app.Action = run
+	app.Commands = []cli.Command{
+		compileCommand,
+		runCommand,
 	}
-
-func run(ctx *cli.Context) error {
-	glogger := log.NewGlogHandler(log.StreamHandler(os.Stderr, log.TerminalFormat(false)))
-	glogger.Verbosity(log.Lvl(ctx.GlobalInt(VerbosityFlag.Name)))
-	log.Root().SetHandler(glogger)
-
-	var (
-		db, _      = ethdb.NewMemDatabase()
-		statedb, _ = state.New(common.Hash{}, db)
-		address    = common.StringToAddress("sender")
-		sender     = vm.AccountRef(address)
-	)
-	statedb.CreateAccount(common.StringToAddress("sender"))
-
-	logger := vm.NewStructLogger(nil)
-
-	tstart := time.Now()
-
-	var (
-		code []byte
-		ret  []byte
-		err  error
-	)
-
-	if ctx.GlobalString(CodeFlag.Name) != "" {
-		code = common.Hex2Bytes(ctx.GlobalString(CodeFlag.Name))
-	} else {
-		var hexcode []byte
-		if ctx.GlobalString(CodeFileFlag.Name) != "" {
-			var err error
-			hexcode, err = ioutil.ReadFile(ctx.GlobalString(CodeFileFlag.Name))
-			if err != nil {
-				fmt.Printf("Could not load code from file: %v\n", err)
-				os.Exit(1)
-			}
-		} else {
-			var err error
-			hexcode, err = ioutil.ReadAll(os.Stdin)
-			if err != nil {
-				fmt.Printf("Could not load code from stdin: %v\n", err)
-				os.Exit(1)
-			}
-		}
-		code = common.Hex2Bytes(string(bytes.TrimRight(hexcode, "\n")))
-	}
-
-	if ctx.GlobalBool(CreateFlag.Name) {
-		input := append(code, common.Hex2Bytes(ctx.GlobalString(InputFlag.Name))...)
-		ret, _, err = runtime.Create(input, &runtime.Config{
-			Origin:   sender.Address(),
-			State:    statedb,
-			GasLimit: ctx.GlobalUint64(GasFlag.Name),
-			GasPrice: utils.GlobalBig(ctx, PriceFlag.Name),
-			Value:    utils.GlobalBig(ctx, ValueFlag.Name),
-			EVMConfig: vm.Config{
-				Tracer:             logger,
-				Debug:              ctx.GlobalBool(DebugFlag.Name),
-				DisableGasMetering: ctx.GlobalBool(DisableGasMeteringFlag.Name),
-			},
-		})
-	} else {
-		receiverAddress := common.StringToAddress("receiver")
-		statedb.CreateAccount(receiverAddress)
-		statedb.SetCode(receiverAddress, code)
-
-		ret, err = runtime.Call(receiverAddress, common.Hex2Bytes(ctx.GlobalString(InputFlag.Name)), &runtime.Config{
-			Origin:   sender.Address(),
-			State:    statedb,
-			GasLimit: ctx.GlobalUint64(GasFlag.Name),
-			GasPrice: utils.GlobalBig(ctx, PriceFlag.Name),
-			Value:    utils.GlobalBig(ctx, ValueFlag.Name),
-			EVMConfig: vm.Config{
-				Tracer:             logger,
-				Debug:              ctx.GlobalBool(DebugFlag.Name),
-				DisableGasMetering: ctx.GlobalBool(DisableGasMeteringFlag.Name),
-			},
-		})
-	}
-	vmdone := time.Since(tstart)
-
-	if ctx.GlobalBool(DumpFlag.Name) {
-		statedb.Commit(true)
-		fmt.Println(string(statedb.Dump()))
-	}
-	vm.StdErrFormat(logger.StructLogs())
-
-	if ctx.GlobalBool(SysStatFlag.Name) {
-		var mem goruntime.MemStats
-		goruntime.ReadMemStats(&mem)
-		fmt.Printf("vm took %v\n", vmdone)
-		fmt.Printf(`alloc:      %d
-tot alloc:  %d
-no. malloc: %d
-heap alloc: %d
-heap objs:  %d
-num gc:     %d
-`, mem.Alloc, mem.TotalAlloc, mem.Mallocs, mem.HeapAlloc, mem.HeapObjects, mem.NumGC)
-	}
-
-	fmt.Printf("OUT: 0x%x", ret)
-	if err != nil {
-		fmt.Printf(" error: %v", err)
-	}
-	fmt.Println()
-	return nil
 }
 
 func main() {

cmd/evm/runner.go

@@ -0,0 +1,145 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of go-ethereum.
+//
+// go-ethereum is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// go-ethereum is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.
+
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"time"
+
+	goruntime "runtime"
+
+	"github.com/ethereum/go-ethereum/cmd/utils"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/core/state"
+	"github.com/ethereum/go-ethereum/core/vm"
+	"github.com/ethereum/go-ethereum/core/vm/runtime"
+	"github.com/ethereum/go-ethereum/ethdb"
+	"github.com/ethereum/go-ethereum/log"
+	cli "gopkg.in/urfave/cli.v1"
+)
+
+var runCommand = cli.Command{
+	Action:      runCmd,
+	Name:        "run",
+	Usage:       "run arbitrary evm binary",
+	ArgsUsage:   "<code>",
+	Description: `The run command runs arbitrary EVM code.`,
+}
+
+func runCmd(ctx *cli.Context) error {
+	glogger := log.NewGlogHandler(log.StreamHandler(os.Stderr, log.TerminalFormat(false)))
+	glogger.Verbosity(log.Lvl(ctx.GlobalInt(VerbosityFlag.Name)))
+	log.Root().SetHandler(glogger)
+
+	var (
+		db, _      = ethdb.NewMemDatabase()
+		statedb, _ = state.New(common.Hash{}, db)
+		sender     = common.StringToAddress("sender")
+		logger     = vm.NewStructLogger(nil)
+		tstart     = time.Now()
+	)
+	statedb.CreateAccount(sender)
+
+	var (
+		code []byte
+		ret  []byte
+		err  error
+	)
+	if ctx.GlobalString(CodeFlag.Name) != "" {
+		code = common.Hex2Bytes(ctx.GlobalString(CodeFlag.Name))
+	} else {
+		var hexcode []byte
+		if ctx.GlobalString(CodeFileFlag.Name) != "" {
+			var err error
+			hexcode, err = ioutil.ReadFile(ctx.GlobalString(CodeFileFlag.Name))
+			if err != nil {
+				fmt.Printf("Could not load code from file: %v\n", err)
+				os.Exit(1)
+			}
+		} else {
+			var err error
+			hexcode, err = ioutil.ReadAll(os.Stdin)
+			if err != nil {
+				fmt.Printf("Could not load code from stdin: %v\n", err)
+				os.Exit(1)
+			}
+		}
+		code = common.Hex2Bytes(string(bytes.TrimRight(hexcode, "\n")))
+	}
+
+	if ctx.GlobalBool(CreateFlag.Name) {
+		input := append(code, common.Hex2Bytes(ctx.GlobalString(InputFlag.Name))...)
+		ret, _, err = runtime.Create(input, &runtime.Config{
+			Origin:   sender,
+			State:    statedb,
+			GasLimit: ctx.GlobalUint64(GasFlag.Name),
+			GasPrice: utils.GlobalBig(ctx, PriceFlag.Name),
+			Value:    utils.GlobalBig(ctx, ValueFlag.Name),
+			EVMConfig: vm.Config{
+				Tracer:             logger,
+				Debug:              ctx.GlobalBool(DebugFlag.Name),
+				DisableGasMetering: ctx.GlobalBool(DisableGasMeteringFlag.Name),
+			},
+		})
+	} else {
+		receiver := common.StringToAddress("receiver")
+		statedb.SetCode(receiver, code)
+
+		ret, err = runtime.Call(receiver, common.Hex2Bytes(ctx.GlobalString(InputFlag.Name)), &runtime.Config{
+			Origin:   sender,
+			State:    statedb,
+			GasLimit: ctx.GlobalUint64(GasFlag.Name),
+			GasPrice: utils.GlobalBig(ctx, PriceFlag.Name),
+			Value:    utils.GlobalBig(ctx, ValueFlag.Name),
+			EVMConfig: vm.Config{
+				Tracer:             logger,
+				Debug:              ctx.GlobalBool(DebugFlag.Name),
+				DisableGasMetering: ctx.GlobalBool(DisableGasMeteringFlag.Name),
+			},
+		})
+	}
+	vmdone := time.Since(tstart)
+
+	if ctx.GlobalBool(DumpFlag.Name) {
+		statedb.Commit(true)
+		fmt.Println(string(statedb.Dump()))
+	}
+	vm.StdErrFormat(logger.StructLogs())
+
+	if ctx.GlobalBool(SysStatFlag.Name) {
+		var mem goruntime.MemStats
+		goruntime.ReadMemStats(&mem)
+		fmt.Printf("vm took %v\n", vmdone)
+		fmt.Printf(`alloc:      %d
+tot alloc:  %d
+no. malloc: %d
+heap alloc: %d
+heap objs:  %d
+num gc:     %d
+`, mem.Alloc, mem.TotalAlloc, mem.Mallocs, mem.HeapAlloc, mem.HeapObjects, mem.NumGC)
+	}
+
+	fmt.Printf("OUT: 0x%x", ret)
+	if err != nil {
+		fmt.Printf(" error: %v", err)
+	}
+	fmt.Println()
+	return nil
+}

core/asm/compiler.go

@@ -1,84 +1,32 @@
-package main
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package asm
 
 import (
 	"errors"
 	"fmt"
-	"io/ioutil"
 	"math/big"
 	"os"
-	"path/filepath"
 	"strings"
 
-	cli "gopkg.in/urfave/cli.v1"
+	"github.com/ethereum/go-ethereum/common/math"
-
-	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/core/vm"
-	"github.com/ethereum/go-ethereum/logger/glog"
 )
 
-var (
-	app *cli.App
-
-	DebugFlag = cli.BoolFlag{
-		Name:  "debug",
-		Usage: "outputs lexer and compiler debug output",
-	}
-	LexFlag = cli.BoolFlag{
-		Name:  "lex",
-		Usage: "displays lex token output",
-	}
-)
-
-func init() {
-	app = cli.NewApp()
-	app.Name = filepath.Base(os.Args[0])
-	app.Author = ""
-	app.Email = ""
-	app.Version = "0.1"
-
-	app.Flags = []cli.Flag{
-		DebugFlag,
-	}
-	app.Action = run
-}
-
-func run(ctx *cli.Context) {
-	var (
-		debug    = ctx.GlobalBool(DebugFlag.Name)
-		lexDebug = ctx.GlobalBool(LexFlag.Name)
-	)
-
-	if len(ctx.Args()) == 0 {
-		glog.Exitln("err: <filename> required")
-	}
-
-	fn := ctx.Args().First()
-	src, err := ioutil.ReadFile(fn)
-	if err != nil {
-		glog.Exitln("err:", err)
-	}
-
-	compiler := newCompiler(debug)
-	compiler.feed(lex(fn, src, lexDebug))
-
-	bin, errors := compiler.compile()
-	if len(errors) > 0 {
-		// report errors
-		for _, err := range errors {
-			fmt.Printf("%s:%v\n", fn, err)
-		}
-		os.Exit(1)
-	}
-	fmt.Println(bin)
-}
-
-func main() {
-	if err := app.Run(os.Args); err != nil {
-		fmt.Fprintln(os.Stderr, err)
-		os.Exit(1)
-	}
-}
-
 // Compiler contains information about the parsed source
 // and holds the tokens for the program.
 type Compiler struct {
@@ -93,14 +41,14 @@ type Compiler struct {
 }
 
 // newCompiler returns a new allocated compiler.
-func newCompiler(debug bool) *Compiler {
+func NewCompiler(debug bool) *Compiler {
 	return &Compiler{
 		labels: make(map[string]int),
 		debug:  debug,
 	}
 }
 
-// feed feeds tokens in to ch and are interpreted by
+// Feed feeds tokens in to ch and are interpreted by
 // the compiler.
 //
 // feed is the first pass in the compile stage as it
@@ -109,11 +57,11 @@ func newCompiler(debug bool) *Compiler {
 // of the jump dests. The labels can than be used in the
 // second stage to push labels and determine the right
 // position.
-func (c *Compiler) feed(ch <-chan token) {
+func (c *Compiler) Feed(ch <-chan token) {
 	for i := range ch {
 		switch i.typ {
 		case number:
-			num := common.String2Big(i.text).Bytes()
+			num := math.MustParseBig256(i.text).Bytes()
 			if len(num) == 0 {
 				num = []byte{0}
 			}
@@ -132,17 +80,17 @@ func (c *Compiler) feed(ch <-chan token) {
 		c.tokens = append(c.tokens, i)
 	}
 	if c.debug {
-		fmt.Sprintln(os.Stderr, "found", len(c.labels), "labels")
+		fmt.Fprintln(os.Stderr, "found", len(c.labels), "labels")
 	}
 }
 
-// compile compiles the current tokens and returns a
+// Compile compiles the current tokens and returns a
 // binary string that can be interpreted by the EVM
 // and an error if it failed.
 //
 // compile is the second stage in the compile phase
 // which compiles the tokens to EVM instructions.
-func (c *Compiler) compile() (string, []error) {
+func (c *Compiler) Compile() (string, []error) {
 	var errors []error
 	// continue looping over the tokens until
 	// the stack has been exhausted.
@@ -206,7 +154,7 @@ func (c *Compiler) compileLine() error {
 
 // compileNumber compiles the number to bytes
 func (c *Compiler) compileNumber(element token) (int, error) {
-	num := common.String2Big(element.text).Bytes()
+	num := math.MustParseBig256(element.text).Bytes()
 	if len(num) == 0 {
 		num = []byte{0}
 	}
@@ -247,7 +195,7 @@ func (c *Compiler) compileElement(element token) error {
 		rvalue := c.next()
 		switch rvalue.typ {
 		case number:
-			value = common.String2Big(rvalue.text).Bytes()
+			value = math.MustParseBig256(rvalue.text).Bytes()
 			if len(value) == 0 {
 				value = []byte{0}
 			}

core/asm/lex_test.go

@@ -0,0 +1,36 @@
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package asm
+
+import "testing"
+
+func lexAll(src string) []token {
+	ch := Lex("test.asm", []byte(src), false)
+
+	var tokens []token
+	for i := range ch {
+		tokens = append(tokens, i)
+	}
+	return tokens
+}
+
+func TestComment(t *testing.T) {
+	tokens := lexAll(";; this is a comment")
+	if len(tokens) != 2 { // {new line, EOF}
+		t.Error("expected no tokens")
+	}
+}

core/asm/lexer.go

@@ -1,4 +1,20 @@
-package main
+// Copyright 2017 The go-ethereum Authors
+// This file is part of the go-ethereum library.
+//
+// The go-ethereum library is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// The go-ethereum library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
+
+package asm
 
 import (
 	"fmt"
@@ -11,7 +27,7 @@ import (
 // stateFn is used through the lifetime of the
 // lexer to parse the different values at the
 // current state.
-type stateFn func(*Lexer) stateFn
+type stateFn func(*lexer) stateFn
 
 // token is emitted when the lexer has discovered
 // a new parsable token. These are delivered over
@@ -62,10 +78,10 @@ var stringtokenTypes = []string{
 	stringValue:      "string",
 }
 
-// Lexer is the basic construct for parsing
+// lexer is the basic construct for parsing
 // source code and turning them in to tokens.
 // Tokens are interpreted by the compiler.
-type Lexer struct {
+type lexer struct {
 	input string // input contains the source code of the program
 
 	tokens chan token // tokens is used to deliver tokens to the listener
@@ -79,9 +95,9 @@ type Lexer struct {
 
 // lex lexes the program by name with the given source. It returns a
 // channel on which the tokens are delivered.
-func lex(name string, source []byte, debug bool) <-chan token {
+func Lex(name string, source []byte, debug bool) <-chan token {
 	ch := make(chan token)
-	l := &Lexer{
+	l := &lexer{
 		input:  string(source),
 		tokens: ch,
 		state:  lexLine,
@@ -100,7 +116,7 @@ func lex(name string, source []byte, debug bool) <-chan token {
 }
 
 // next returns the next rune in the program's source.
-func (l *Lexer) next() (rune rune) {
+func (l *lexer) next() (rune rune) {
 	if l.pos >= len(l.input) {
 		l.width = 0
 		return 0
@@ -111,24 +127,24 @@ func (l *Lexer) next() (rune rune) {
 }
 
 // backup backsup the last parsed element (multi-character)
-func (l *Lexer) backup() {
+func (l *lexer) backup() {
 	l.pos -= l.width
 }
 
 // peek returns the next rune but does not advance the seeker
-func (l *Lexer) peek() rune {
+func (l *lexer) peek() rune {
 	r := l.next()
 	l.backup()
 	return r
 }
 
 // ignore advances the seeker and ignores the value
-func (l *Lexer) ignore() {
+func (l *lexer) ignore() {
 	l.start = l.pos
 }
 
 // Accepts checks whether the given input matches the next rune
-func (l *Lexer) accept(valid string) bool {
+func (l *lexer) accept(valid string) bool {
 	if strings.IndexRune(valid, l.next()) >= 0 {
 		return true
 	}
@@ -140,7 +156,7 @@ func (l *Lexer) accept(valid string) bool {
 
 // acceptRun will continue to advance the seeker until valid
 // can no longer be met.
-func (l *Lexer) acceptRun(valid string) {
+func (l *lexer) acceptRun(valid string) {
 	for strings.IndexRune(valid, l.next()) >= 0 {
 	}
 	l.backup()
@@ -148,7 +164,7 @@ func (l *Lexer) acceptRun(valid string) {
 
 // acceptRunUntil is the inverse of acceptRun and will continue
 // to advance the seeker until the rune has been found.
-func (l *Lexer) acceptRunUntil(until rune) bool {
+func (l *lexer) acceptRunUntil(until rune) bool {
 	// Continues running until a rune is found
 	for i := l.next(); strings.IndexRune(string(until), i) == -1; i = l.next() {
 		if i == 0 {
@@ -160,12 +176,12 @@ func (l *Lexer) acceptRunUntil(until rune) bool {
 }
 
 // blob returns the current value
-func (l *Lexer) blob() string {
+func (l *lexer) blob() string {
 	return l.input[l.start:l.pos]
 }
 
 // Emits a new token on to token channel for processing
-func (l *Lexer) emit(t tokenType) {
+func (l *lexer) emit(t tokenType) {
 	token := token{t, l.lineno, l.blob()}
 
 	if l.debug {
@@ -177,7 +193,7 @@ func (l *Lexer) emit(t tokenType) {
 }
 
 // lexLine is state function for lexing lines
-func lexLine(l *Lexer) stateFn {
+func lexLine(l *lexer) stateFn {
 	for {
 		switch r := l.next(); {
 		case r == '\n':
@@ -207,7 +223,7 @@ func lexLine(l *Lexer) stateFn {
 
 // lexComment parses the current position until the end
 // of the line and discards the text.
-func lexComment(l *Lexer) stateFn {
+func lexComment(l *lexer) stateFn {
 	l.acceptRunUntil('\n')
 	l.ignore()
 
@@ -217,7 +233,7 @@ func lexComment(l *Lexer) stateFn {
 // lexLabel parses the current label, emits and returns
 // the lex text state function to advance the parsing
 // process.
-func lexLabel(l *Lexer) stateFn {
+func lexLabel(l *lexer) stateFn {
 	l.acceptRun(Alpha + "_")
 
 	l.emit(label)
@@ -228,7 +244,7 @@ func lexLabel(l *Lexer) stateFn {
 // lexInsideString lexes the inside of a string until
 // until the state function finds the closing quote.
 // It returns the lex text state function.
-func lexInsideString(l *Lexer) stateFn {
+func lexInsideString(l *lexer) stateFn {
 	if l.acceptRunUntil('"') {
 		l.emit(stringValue)
 	}
@@ -236,7 +252,7 @@ func lexInsideString(l *Lexer) stateFn {
 	return lexLine
 }
 
-func lexNumber(l *Lexer) stateFn {
+func lexNumber(l *lexer) stateFn {
 	acceptance := Numbers
 	if l.accept("0") && l.accept("xX") {
 		acceptance = HexadecimalNumbers
@@ -248,7 +264,7 @@ func lexNumber(l *Lexer) stateFn {
 	return lexLine
 }
 
-func lexElement(l *Lexer) stateFn {
+func lexElement(l *lexer) stateFn {
 	l.acceptRun(Alpha + "_" + Numbers)
 
 	if l.peek() == ':' {