Add logging, default Lua file, node prev/next

.gitignore

@@ -1,3 +1,6 @@
 .vscode
 *.code-workspace
 dist/
+store/
+playground/
+bin/

Rakefile

@@ -0,0 +1,26 @@
+@versions = {}
+
+File.read("version").each_line do |line|
+	product,versionnumber = line.chomp.split(/=/)
+	@versions[product]=versionnumber
+end
+
+@ets_version = @versions['ets_version']
+
+desc "Show rake description"
+task :default do
+	puts
+	puts "Run 'rake -T' for a list of tasks."
+	puts
+	puts "1: Use 'rake build' to build the 'ets' binary. That should be\n   the starting point."
+	puts
+end
+
+
+desc "Compile and install necessary software"
+task :build  do
+	sh "go build -ldflags \"-X main.version=#{@ets_version}\" -o bin/ets github.com/speedata/ets/ets/ets"
+end
+
+
+

Readme.md

@@ -3,24 +3,25 @@
 This software repository contains a Lua frontend for the typesetting library [“Boxes and Glue”](https://github.com/speedata/boxesandglue) which is an algorithmic typesetting machine in the spirits of TeX.
 
 
-## Build
+## Running the software
 
-You just need Go installed on your system, clone the repository and run
+Download the software ([get the latest release here](https://github.com/speedata/ets/releases)), unzip the archive and call
 
-    go build -o bin/ets github.com/speedata/ets/ets/ets
+    bin/ets myscript.lua
 
+on the command line.
 
-## Running the software
+## Build
 
-call
+You just need Go installed on your system, clone the repository and run
+
+    go build -o bin/ets github.com/speedata/ets/ets/ets
 
-    bin/ets myscript.lua
 
-on the command line
 
 ## Status
 
-This software is more or less a demo of the architecture and usable for any serious purpose yet.
+This software is more or less a demo of the architecture and not usable for any serious purpose yet.
 
 Feedback welcome!
 

core/core.go

@@ -1,15 +1,51 @@
 package core
 
 import (
+	"os"
+	"path/filepath"
+
+	"github.com/speedata/boxesandglue/backend/bag"
 	lua "github.com/yuin/gopher-lua"
+	"go.uber.org/zap"
+	"go.uber.org/zap/zapcore"
 )
 
-// Dothings opens the Lua file and executes it
-func Dothings(luafile string) error {
+// Runs the Lua file if it exists. If the exename is "foo", it looks for a Lua file called "foo.lua"
+func runDefaultLua(l *lua.LState, exename string) error {
+	var extension = filepath.Ext(exename)
+	var name = exename[0:len(exename)-len(extension)] + ".lua"
+	var err error
+	if _, err = os.Stat(name); err != nil {
+		return nil
+	}
+	return l.DoFile(name)
+}
+
+func newZapLogger() *zap.SugaredLogger {
+	logger, _ := zap.Config{
+		Level:       zap.NewAtomicLevelAt(zapcore.DebugLevel),
+		Encoding:    "console",
+		OutputPaths: []string{"stdout"},
+		EncoderConfig: zapcore.EncoderConfig{
+			EncodeLevel: zapcore.LowercaseColorLevelEncoder,
+			LevelKey:    "level",
+			MessageKey:  "message",
+		},
+	}.Build()
+	return logger.Sugar()
+}
 
+// Dothings opens the Lua file and executes it
+func Dothings(luafile string, exename string) error {
 	l := lua.NewState()
+	bag.Logger = newZapLogger()
 	registerDocumentType(l)
 	registerNodeType(l)
+
+	if err := runDefaultLua(l, exename); err != nil {
+		return err
+	}
+
 	if err := l.DoFile(luafile); err != nil {
 		return err
 	}

core/document.go

@@ -27,6 +27,7 @@ const (
 func registerDocumentType(l *lua.LState) {
 	mt := l.NewTypeMetatable(luaDocumentTypeName)
 	l.SetGlobal("document", mt)
+	l.SetField(mt, "info", l.NewFunction(documentInfo))
 	l.SetField(mt, "new", l.NewFunction(newDocument))
 	l.SetField(mt, "sp", l.NewFunction(documentSP))
 	l.SetField(mt, "__index", l.NewFunction(indexDoc))
@@ -35,27 +36,39 @@ func registerDocumentType(l *lua.LState) {
 // Constructor
 func newDocument(l *lua.LState) int {
 	doc := &doc{}
-	lv := l.Get(-1)
+	filename := l.CheckString(1)
 	var w *os.File
 	var err error
-	if str, ok := lv.(lua.LString); ok {
-		w, err = os.Create(string(str))
-		if err != nil {
-			return lerr(l, err.Error())
-		}
-	} else {
-		l.TypeError(1, lua.LTString)
-		return 0
+	w, err = os.Create(filename)
+	if err != nil {
+		return lerr(l, err.Error())
 	}
 	doc.w = w
 	doc.d = document.NewDocument(w)
+	doc.d.Filename = filename
 	ud := l.NewUserData()
 	ud.Value = doc
 	l.SetMetatable(ud, l.GetTypeMetatable(luaDocumentTypeName))
 	l.Push(ud)
 	return 1
 }
 
+func documentSP(l *lua.LState) int {
+	arg := l.CheckString(1)
+	size, err := bag.Sp(arg)
+	if err != nil {
+		return lerr(l, err.Error())
+	}
+	l.Push(lua.LNumber(size))
+	return 1
+}
+
+func documentInfo(l *lua.LState) int {
+	str := l.CheckString(1)
+	bag.Logger.Info(str)
+	return 0
+}
+
 func indexDoc(l *lua.LState) int {
 	doc := checkDocument(l, 1)
 	switch arg := l.CheckString(2); arg {
@@ -115,16 +128,6 @@ func documentFinish(d *doc) lua.LGFunction {
 	}
 }
 
-func documentSP(l *lua.LState) int {
-	arg := l.CheckString(1)
-	size, err := bag.Sp(arg)
-	if err != nil {
-		return lerr(l, err.Error())
-	}
-	l.Push(lua.LNumber(size))
-	return 1
-}
-
 func documentLoadPatternFile(doc *document.Document) lua.LGFunction {
 	return func(l *lua.LState) int {
 		fn := l.CheckString(1)