Formatter option is now composed of two data: flags (lower 16 bits) and indentation size (higher 16 bits).

DictType and ListType formatter use both indent and flag options.
Simple-store now makes a DictType from its data and its ToString() function returns dict.ToString()

builtin-base.go

@@ -67,7 +67,7 @@ func boolFunc(ctx ExprContext, name string, args []any) (result any, err error)
 	case string:
 		result = len(v) > 0
 	default:
-		err = errCantConvert(name, v, "bool")
+		err = ErrCantConvert(name, v, "bool")
 	}
 	return
 }
@@ -90,7 +90,7 @@ func intFunc(ctx ExprContext, name string, args []any) (result any, err error) {
 			result = int64(i)
 		}
 	default:
-		err = errCantConvert(name, v, "int")
+		err = ErrCantConvert(name, v, "int")
 	}
 	return
 }
@@ -115,7 +115,7 @@ func decFunc(ctx ExprContext, name string, args []any) (result any, err error) {
 	case *FractionType:
 		result = v.toFloat()
 	default:
-		err = errCantConvert(name, v, "float")
+		err = ErrCantConvert(name, v, "float")
 	}
 	return
 }
@@ -127,9 +127,9 @@ func fractFunc(ctx ExprContext, name string, args []any) (result any, err error)
 		if len(args) > 1 {
 			var ok bool
 			if den, ok = args[1].(int64); !ok {
-				err = errExpectedGot(name, "integer", args[1])
+				err = ErrExpectedGot(name, "integer", args[1])
 			} else if den == 0 {
-				err = errFuncDivisionByZero(name)
+				err = ErrFuncDivisionByZero(name)
 			}
 		}
 		if err == nil {
@@ -148,7 +148,7 @@ func fractFunc(ctx ExprContext, name string, args []any) (result any, err error)
 	case *FractionType:
 		result = v
 	default:
-		err = errCantConvert(name, v, "float")
+		err = ErrCantConvert(name, v, "float")
 	}
 	return
 }

builtin-string.go

@@ -21,7 +21,7 @@ func doJoinStr(funcName string, sep string, it Iterator) (result any, err error)
 		if s, ok := v.(string); ok {
 			sb.WriteString(s)
 		} else {
-			err = errExpectedGot(funcName, TypeString, v)
+			err = ErrExpectedGot(funcName, TypeString, v)
 			return
 		}
 	}
@@ -45,13 +45,13 @@ func joinStrFunc(ctx ExprContext, name string, args []any) (result any, err erro
 			} else if it, ok := args[1].(Iterator); ok {
 				result, err = doJoinStr(name, sep, it)
 			} else {
-				err = errInvalidParameterValue(name, ParamParts, args[1])
+				err = ErrInvalidParameterValue(name, ParamParts, args[1])
 			}
 		} else {
 			result, err = doJoinStr(name, sep, NewArrayIterator(args[1:]))
 		}
 	} else {
-		err = errWrongParamType(name, ParamSeparator, TypeString, args[0])
+		err = ErrWrongParamType(name, ParamSeparator, TypeString, args[0])
 	}
 	return
 }
@@ -63,14 +63,14 @@ func subStrFunc(ctx ExprContext, name string, args []any) (result any, err error
 	var ok bool
 
 	if source, ok = args[0].(string); !ok {
-		return nil, errWrongParamType(name, ParamSource, TypeString, args[0])
+		return nil, ErrWrongParamType(name, ParamSource, TypeString, args[0])
 	}
 
-	if start, err = toInt(args[1], name+"()"); err != nil {
+	if start, err = ToInt(args[1], name+"()"); err != nil {
 		return
 	}
 
-	if count, err = toInt(args[2], name+"()"); err != nil {
+	if count, err = ToInt(args[2], name+"()"); err != nil {
 		return
 	}
 
@@ -91,7 +91,7 @@ func trimStrFunc(ctx ExprContext, name string, args []any) (result any, err erro
 	var ok bool
 
 	if source, ok = args[0].(string); !ok {
-		return nil, errWrongParamType(name, ParamSource, TypeString, args[0])
+		return nil, ErrWrongParamType(name, ParamSource, TypeString, args[0])
 	}
 	result = strings.TrimSpace(source)
 	return
@@ -104,7 +104,7 @@ func startsWithStrFunc(ctx ExprContext, name string, args []any) (result any, er
 	result = false
 
 	if source, ok = args[0].(string); !ok {
-		return result, errWrongParamType(name, ParamSource, TypeString, args[0])
+		return result, ErrWrongParamType(name, ParamSource, TypeString, args[0])
 	}
 	for i, targetSpec := range args[1:] {
 		if target, ok := targetSpec.(string); ok {
@@ -127,7 +127,7 @@ func endsWithStrFunc(ctx ExprContext, name string, args []any) (result any, err
 	result = false
 
 	if source, ok = args[0].(string); !ok {
-		return result, errWrongParamType(name, ParamSource, TypeString, args[0])
+		return result, ErrWrongParamType(name, ParamSource, TypeString, args[0])
 	}
 	for i, targetSpec := range args[1:] {
 		if target, ok := targetSpec.(string); ok {
@@ -150,7 +150,7 @@ func splitStrFunc(ctx ExprContext, name string, args []any) (result any, err err
 	var ok bool
 
 	if source, ok = args[0].(string); !ok {
-		return result, errWrongParamType(name, ParamSource, TypeString, args[0])
+		return result, ErrWrongParamType(name, ParamSource, TypeString, args[0])
 	}
 
 	if sep, ok = args[1].(string); !ok {
@@ -182,34 +182,34 @@ func splitStrFunc(ctx ExprContext, name string, args []any) (result any, err err
 
 // Import above functions in the context
 func ImportStringFuncs(ctx ExprContext) {
-	ctx.RegisterFunc("joinStr", NewGolangFunctor(joinStrFunc), TypeString, []ExprFuncParam{
+	ctx.RegisterFunc("strJoin", NewGolangFunctor(joinStrFunc), TypeString, []ExprFuncParam{
 		NewFuncParam(ParamSeparator),
 		NewFuncParamFlag(ParamItem, PfRepeat),
 	})
 
-	ctx.RegisterFunc("subStr", NewGolangFunctor(subStrFunc), TypeString, []ExprFuncParam{
+	ctx.RegisterFunc("strSub", NewGolangFunctor(subStrFunc), TypeString, []ExprFuncParam{
 		NewFuncParam(ParamSource),
 		NewFuncParamFlagDef(ParamStart, PfDefault, int64(0)),
 		NewFuncParamFlagDef(ParamCount, PfDefault, int64(-1)),
 	})
 
-	ctx.RegisterFunc("splitStr", NewGolangFunctor(splitStrFunc), "list of "+TypeString, []ExprFuncParam{
+	ctx.RegisterFunc("strSplit", NewGolangFunctor(splitStrFunc), "list of "+TypeString, []ExprFuncParam{
 		NewFuncParam(ParamSource),
 		NewFuncParamFlagDef(ParamSeparator, PfDefault, ""),
 		NewFuncParamFlagDef(ParamCount, PfDefault, int64(-1)),
 	})
 
-	ctx.RegisterFunc("trimStr", NewGolangFunctor(trimStrFunc), TypeString, []ExprFuncParam{
+	ctx.RegisterFunc("strTrim", NewGolangFunctor(trimStrFunc), TypeString, []ExprFuncParam{
 		NewFuncParam(ParamSource),
 	})
 
-	ctx.RegisterFunc("startsWithStr", NewGolangFunctor(startsWithStrFunc), TypeBoolean, []ExprFuncParam{
+	ctx.RegisterFunc("strStartsWith", NewGolangFunctor(startsWithStrFunc), TypeBoolean, []ExprFuncParam{
 		NewFuncParam(ParamSource),
 		NewFuncParam(ParamPrefix),
 		NewFuncParamFlag("other "+ParamPrefix, PfRepeat),
 	})
 
-	ctx.RegisterFunc("endsWithStr", NewGolangFunctor(endsWithStrFunc), TypeBoolean, []ExprFuncParam{
+	ctx.RegisterFunc("strEndsWith", NewGolangFunctor(endsWithStrFunc), TypeBoolean, []ExprFuncParam{
 		NewFuncParam(ParamSource),
 		NewFuncParam(ParamSuffix),
 		NewFuncParamFlag("other "+ParamSuffix, PfRepeat),

common-errors.go

@@ -8,7 +8,7 @@ import (
 	"fmt"
 )
 
-func errTooFewParams(funcName string, minArgs, maxArgs, argCount int) (err error) {
+func ErrTooFewParams(funcName string, minArgs, maxArgs, argCount int) (err error) {
 	if maxArgs < 0 {
 		err = fmt.Errorf("%s(): too few params -- expected %d or more, got %d", funcName, minArgs, argCount)
 	} else {
@@ -17,39 +17,39 @@ func errTooFewParams(funcName string, minArgs, maxArgs, argCount int) (err error
 	return
 }
 
-func errTooMuchParams(funcName string, maxArgs, argCount int) (err error) {
+func ErrTooMuchParams(funcName string, maxArgs, argCount int) (err error) {
 	err = fmt.Errorf("%s(): too much params -- expected %d, got %d", funcName, maxArgs, argCount)
 	return
 }
 
 // --- General errors
 
-func errCantConvert(funcName string, value any, kind string) error {
+func ErrCantConvert(funcName string, value any, kind string) error {
 	return fmt.Errorf("%s(): can't convert %s to %s", funcName, TypeName(value), kind)
 }
 
-func errExpectedGot(funcName string, kind string, value any) error {
+func ErrExpectedGot(funcName string, kind string, value any) error {
-	return fmt.Errorf("%s() expected %s, got %s (%v)", funcName, kind, TypeName(value), value)
+	return fmt.Errorf("%s(): expected %s, got %s (%v)", funcName, kind, TypeName(value), value)
 }
 
-func errFuncDivisionByZero(funcName string) error {
+func ErrFuncDivisionByZero(funcName string) error {
 	return fmt.Errorf("%s(): division by zero", funcName)
 }
 
-func errDivisionByZero() error {
+func ErrDivisionByZero() error {
 	return fmt.Errorf("division by zero")
 }
 
 // --- Parameter errors
 
-func errMissingRequiredParameter(funcName, paramName string) error {
+func ErrMissingRequiredParameter(funcName, paramName string) error {
-	return fmt.Errorf("%s() missing required parameter %q", funcName, paramName)
+	return fmt.Errorf("%s(): missing required parameter %q", funcName, paramName)
 }
 
-func errInvalidParameterValue(funcName, paramName string, paramValue any) error {
+func ErrInvalidParameterValue(funcName, paramName string, paramValue any) error {
-	return fmt.Errorf("%s() invalid value %s (%v) for parameter %q", funcName, TypeName(paramValue), paramValue, paramName)
+	return fmt.Errorf("%s(): invalid value %s (%v) for parameter %q", funcName, TypeName(paramValue), paramValue, paramName)
 }
 
-func errWrongParamType(funcName, paramName, paramType string, paramValue any) error {
+func ErrWrongParamType(funcName, paramName, paramType string, paramValue any) error {
-	return fmt.Errorf("%s() the %q parameter must be a %s, got a %s (%v)", funcName, paramName, paramType, TypeName(paramValue), paramValue)
+	return fmt.Errorf("%s(): the %q parameter must be a %s, got a %s (%v)", funcName, paramName, paramType, TypeName(paramValue), paramValue)
 }

dict-type.go

@@ -32,9 +32,16 @@ func newDict(dictAny map[any]*term) (dict *DictType) {
 	return
 }
 
-func (dict *DictType) toMultiLine(sb *strings.Builder, indent int) {
+func (dict *DictType) toMultiLine(sb *strings.Builder, opt FmtOpt) {
-	sb.WriteString(strings.Repeat("\t", indent))
+	indent := GetFormatIndent(opt)
-	sb.WriteString("{\n")
+	flags := GetFormatFlags(opt)
+	//sb.WriteString(strings.Repeat("  ", indent))
+	sb.WriteByte('{')
+
+	if len(*dict) > 0 {
+		innerOpt := MakeFormatOptions(flags, indent+1)
+		nest := strings.Repeat("  ", indent+1)
+		sb.WriteByte('\n')
 
 		first := true
 		for name, value := range *dict {
@@ -45,7 +52,7 @@ func (dict *DictType) toMultiLine(sb *strings.Builder, indent int) {
 				sb.WriteByte('\n')
 			}
 
-		sb.WriteString(strings.Repeat("\t", indent+1))
+			sb.WriteString(nest)
 			if key, ok := name.(string); ok {
 				sb.WriteString(string('"') + key + string('"'))
 			} else {
@@ -53,21 +60,24 @@ func (dict *DictType) toMultiLine(sb *strings.Builder, indent int) {
 			}
 			sb.WriteString(": ")
 			if f, ok := value.(Formatter); ok {
-			sb.WriteString(f.ToString(MultiLine))
+				sb.WriteString(f.ToString(innerOpt))
 			} else if _, ok = value.(Functor); ok {
 				sb.WriteString("func(){}")
 			} else {
 				sb.WriteString(fmt.Sprintf("%v", value))
 			}
 		}
-	sb.WriteString(strings.Repeat("\t", indent))
+		sb.WriteByte('\n')
-	sb.WriteString("\n}")
+		sb.WriteString(strings.Repeat("  ", indent))
+	}
+	sb.WriteString("}")
 }
 
 func (dict *DictType) ToString(opt FmtOpt) string {
 	var sb strings.Builder
-	if opt&MultiLine != 0 {
+	flags := GetFormatFlags(opt)
-		dict.toMultiLine(&sb, 0)
+	if flags&MultiLine != 0 {
+		dict.toMultiLine(&sb, opt)
 	} else {
 		sb.WriteByte('{')
 		first := true
@@ -133,3 +143,9 @@ func (dict *DictType) setItem(key any, value any) (err error) {
 	(*dict)[key] = value
 	return
 }
+
+////////////////
+
+type DictFormat interface {
+	ToDict() *DictType
+}

formatter.go

@@ -6,7 +6,7 @@ package expr
 
 import "fmt"
 
-type FmtOpt uint16
+type FmtOpt uint32 // lower 16 bits hold a bit-mask, higher 16 bits hold an indentation number
 
 const (
 	TTY FmtOpt = 1 << iota
@@ -30,6 +30,18 @@ func TruncateString(s string) (trunc string) {
 	return
 }
 
+func MakeFormatOptions(flags FmtOpt, indent int) FmtOpt {
+	return FmtOpt(indent<<16) | flags
+}
+
+func GetFormatFlags(opt FmtOpt) FmtOpt {
+	return opt & 0xFFFF
+}
+
+func GetFormatIndent(opt FmtOpt) int {
+	return int(opt >> 16)
+}
+
 type Formatter interface {
 	ToString(options FmtOpt) string
 }

fraction-type.go

@@ -70,7 +70,7 @@ func makeGeneratingFraction(s string) (f *FractionType, err error) {
 			}
 			for _, c := range dec[0:lsd] {
 				if c < '0' || c > '9' {
-					return nil, errExpectedGot("fract", "digit", c)
+					return nil, ErrExpectedGot("fract", "digit", c)
 				}
 				num = num*10 + int64(c-'0')
 				den = den * 10
@@ -81,7 +81,7 @@ func makeGeneratingFraction(s string) (f *FractionType, err error) {
 			mul := int64(1)
 			for _, c := range subParts[0] {
 				if c < '0' || c > '9' {
-					return nil, errExpectedGot("fract", "digit", c)
+					return nil, ErrExpectedGot("fract", "digit", c)
 				}
 				num = num*10 + int64(c-'0')
 				sub = sub*10 + int64(c-'0')
@@ -94,7 +94,7 @@ func makeGeneratingFraction(s string) (f *FractionType, err error) {
 				p := subParts[1][0 : len(subParts[1])-1]
 				for _, c := range p {
 					if c < '0' || c > '9' {
-						return nil, errExpectedGot("fract", "digit", c)
+						return nil, ErrExpectedGot("fract", "digit", c)
 					}
 					num = num*10 + int64(c-'0')
 					den = den*10 + 9
@@ -212,7 +212,7 @@ func anyToFract(v any) (f *FractionType, err error) {
 		}
 	}
 	if f == nil {
-		err = errExpectedGot("fract", TypeFraction, v)
+		err = ErrExpectedGot("fract", TypeFraction, v)
 	}
 	return
 }

function.go

@@ -21,7 +21,7 @@ func (functor *baseFunctor) ToString(opt FmtOpt) (s string) {
 	if functor.info != nil {
 		s = functor.info.ToString(opt)
 	} else {
-		s = "func() {<body>}"
+		s = "func() {}"
 	}
 	return s
 }
@@ -180,7 +180,7 @@ func (info *funcInfo) ToString(opt FmtOpt) string {
 	} else {
 		sb.WriteString(TypeAny)
 	}
-	sb.WriteString(" {<body>}")
+	sb.WriteString(" {}")
 	return sb.String()
 }
 

iter-list.go

@@ -26,21 +26,21 @@ func NewListIterator(list *ListType, args []any) (it *ListIterator) {
 	}
 	it = &ListIterator{a: list, count: 0, index: -1, start: 0, stop: listLen - 1, step: 1}
 	if argc >= 1 {
-		if i, err := toInt(args[0], "start index"); err == nil {
+		if i, err := ToInt(args[0], "start index"); err == nil {
 			if i < 0 {
 				i = listLen + i
 			}
 			it.start = i
 		}
 		if argc >= 2 {
-			if i, err := toInt(args[1], "stop index"); err == nil {
+			if i, err := ToInt(args[1], "stop index"); err == nil {
 				if i < 0 {
 					i = listLen + i
 				}
 				it.stop = i
 			}
 			if argc >= 3 {
-				if i, err := toInt(args[2], "step"); err == nil {
+				if i, err := ToInt(args[2], "step"); err == nil {
 					if i < 0 {
 						i = -i
 					}

list-type.go

@@ -52,16 +52,24 @@ func ListFromStrings(stringList []string) (list *ListType) {
 }
 
 func (ls *ListType) ToString(opt FmtOpt) (s string) {
+        indent := GetFormatIndent(opt)
+        flags := GetFormatFlags(opt)
+
 	var sb strings.Builder
 	sb.WriteByte('[')
 	if len(*ls) > 0 {
-		if opt&MultiLine != 0 {
+                innerOpt := MakeFormatOptions(flags, indent+1)
-			sb.WriteString("\n  ")
+                nest := strings.Repeat("  ", indent+1)
+
+		if flags&MultiLine != 0 {
+			sb.WriteByte('\n')
+			sb.WriteString(nest)
 		}
 		for i, item := range []any(*ls) {
 			if i > 0 {
-				if opt&MultiLine != 0 {
+				if flags&MultiLine != 0 {
-					sb.WriteString(",\n  ")
+					sb.WriteString(",\n")
+					sb.WriteString(nest)
 				} else {
 					sb.WriteString(", ")
 				}
@@ -70,17 +78,20 @@ func (ls *ListType) ToString(opt FmtOpt) (s string) {
 				sb.WriteByte('"')
 				sb.WriteString(s)
 				sb.WriteByte('"')
+			} else if formatter, ok := item.(Formatter); ok {
+				sb.WriteString(formatter.ToString(innerOpt))
 			} else {
 				sb.WriteString(fmt.Sprintf("%v", item))
 			}
 		}
-		if opt&MultiLine != 0 {
+		if flags&MultiLine != 0 {
 			sb.WriteByte('\n')
+			sb.WriteString(strings.Repeat("  ", indent))
 		}
 	}
 	sb.WriteByte(']')
 	s = sb.String()
-	if opt&Truncate != 0 && len(s) > TruncateSize {
+	if flags&Truncate != 0 && len(s) > TruncateSize {
 		s = TruncateString(s)
 	}
 	return

operand-func.go

@@ -26,7 +26,7 @@ func checkFunctionCall(ctx ExprContext, name string, varParams *[]any) (err erro
 	if info, exists, owner := GetFuncInfo(ctx, name); exists {
 		passedCount := len(*varParams)
 		if info.MinArgs() > passedCount {
-			err = errTooFewParams(name, info.MinArgs(), info.MaxArgs(), passedCount)
+			err = ErrTooFewParams(name, info.MinArgs(), info.MaxArgs(), passedCount)
 		}
 		for i, p := range info.Params() {
 			if i >= passedCount {
@@ -37,7 +37,7 @@ func checkFunctionCall(ctx ExprContext, name string, varParams *[]any) (err erro
 			}
 		}
 		if err == nil && info.MaxArgs() >= 0 && info.MaxArgs() < len(*varParams) {
-			err = errTooMuchParams(name, info.MaxArgs(), len(*varParams))
+			err = ErrTooMuchParams(name, info.MaxArgs(), len(*varParams))
 		}
 		if err == nil && owner != ctx {
 			ctx.RegisterFuncInfo(info)

operator-bool.go

@@ -25,7 +25,7 @@ func evalNot(ctx ExprContext, self *term) (v any, err error) {
 		return
 	}
 
-	if b, ok := toBool(rightValue); ok {
+	if b, ok := ToBool(rightValue); ok {
 		v = !b
 	} else {
 		err = self.errIncompatibleType(rightValue)
@@ -65,8 +65,8 @@ func evalAndWithoutShortcut(ctx ExprContext, self *term) (v any, err error) {
 		return
 	}
 
-	leftBool, lok = toBool(leftValue)
+	leftBool, lok = ToBool(leftValue)
-	rightBool, rok = toBool(rightValue)
+	rightBool, rok = ToBool(rightValue)
 
 	if lok && rok {
 		v = leftBool && rightBool
@@ -87,13 +87,13 @@ func evalAndWithShortcut(ctx ExprContext, self *term) (v any, err error) {
 		return
 	}
 
-	if leftBool, lok := toBool(leftValue); !lok {
+	if leftBool, lok := ToBool(leftValue); !lok {
 		err = fmt.Errorf("got %T as left operand type of 'and' operator, it must be bool", leftBool)
 		return
 	} else if !leftBool {
 		v = false
 	} else if rightValue, err = self.children[1].compute(ctx); err == nil {
-		if rightBool, rok := toBool(rightValue); rok {
+		if rightBool, rok := ToBool(rightValue); rok {
 			v = rightBool
 		} else {
 			err = self.errIncompatibleTypes(leftValue, rightValue)
@@ -134,8 +134,8 @@ func evalOrWithoutShortcut(ctx ExprContext, self *term) (v any, err error) {
 		return
 	}
 
-	leftBool, lok = toBool(leftValue)
+	leftBool, lok = ToBool(leftValue)
-	rightBool, rok = toBool(rightValue)
+	rightBool, rok = ToBool(rightValue)
 
 	if lok && rok {
 		v = leftBool || rightBool
@@ -156,13 +156,13 @@ func evalOrWithShortcut(ctx ExprContext, self *term) (v any, err error) {
 		return
 	}
 
-	if leftBool, lok := toBool(leftValue); !lok {
+	if leftBool, lok := ToBool(leftValue); !lok {
 		err = fmt.Errorf("got %T as left operand type of 'or' operator, it must be bool", leftBool)
 		return
 	} else if leftBool {
 		v = true
 	} else if rightValue, err = self.children[1].compute(ctx); err == nil {
-		if rightBool, rok := toBool(rightValue); rok {
+		if rightBool, rok := ToBool(rightValue); rok {
 			v = rightBool
 		} else {
 			err = self.errIncompatibleTypes(leftValue, rightValue)

operator-context.go

@@ -31,7 +31,9 @@ func evalContextValue(ctx ExprContext, self *term) (v any, err error) {
 	}
 
 	if sourceCtx != nil {
-		if formatter, ok := sourceCtx.(Formatter); ok {
+		if formatter, ok := sourceCtx.(DictFormat); ok {
+			v = formatter.ToDict()
+		} else if formatter, ok := sourceCtx.(Formatter); ok {
 			v = formatter.ToString(0)
 		} else {
 			// keys := sourceCtx.EnumVars(func(name string) bool { return name[0] != '_' })

operator-index.go

@@ -23,7 +23,7 @@ func verifyKey(indexTerm *term, indexList *ListType) (index any, err error) {
 func verifyIndex(indexTerm *term, indexList *ListType, maxValue int) (index int, err error) {
 	var v int
 
-	if v, err = toInt((*indexList)[0], "index expression"); err == nil {
+	if v, err = ToInt((*indexList)[0], "index expression"); err == nil {
 		if v < 0 && v >= -maxValue {
 			v = maxValue + v
 		}

operator-length.go

@@ -36,7 +36,7 @@ func evalLength(ctx ExprContext, self *term) (v any, err error) {
 	} else if it, ok := childValue.(Iterator); ok {
 		if extIt, ok := childValue.(ExtIterator); ok && extIt.HasOperation(countName) {
 			count, _ := extIt.CallOperation(countName, nil)
-			v, _ = toInt(count, "")
+			v, _ = ToInt(count, "")
 		} else {
 			v = int64(it.Index() + 1)
 		}

operator-rel.go

@@ -70,7 +70,7 @@ func newNotEqualTerm(tk *Token) (inst *term) {
 
 func evalNotEqual(ctx ExprContext, self *term) (v any, err error) {
 	if v, err = evalEqual(ctx, self); err == nil {
-		b, _ := toBool(v)
+		b, _ := ToBool(v)
 		v = !b
 	}
 	return

scanner.go

@@ -178,13 +178,18 @@ func (self *scanner) fetchNextToken() (tk *Token) {
 				tk = self.makeToken(SymDot, ch)
 			}
 		case '\'':
+			if escape {
 				tk = self.makeToken(SymQuote, ch)
+				escape = false
+			} else {
+				tk = self.fetchString(ch)
+			}
 		case '"':
 			if escape {
 				tk = self.makeToken(SymDoubleQuote, ch)
 				escape = false
 			} else {
-				tk = self.fetchString()
+				tk = self.fetchString(ch)
 			}
 		case '`':
 			tk = self.makeToken(SymBackTick, ch)
@@ -533,7 +538,7 @@ func (self *scanner) fetchUntil(sym Symbol, allowEos bool, endings ...byte) (tk
 	return
 }
 
-func (self *scanner) fetchString() (tk *Token) {
+func (self *scanner) fetchString(termCh byte) (tk *Token) {
 	var err error
 	var ch, prev byte
 	var sb strings.Builder
@@ -554,7 +559,7 @@ func (self *scanner) fetchString() (tk *Token) {
 				sb.WriteByte(ch)
 			}
 			prev = 0
-		} else if ch == '"' {
+		} else if ch == termCh {
 			break
 		} else {
 			prev = ch

simple-store.go

@@ -7,7 +7,7 @@ package expr
 import (
 	"fmt"
 	"slices"
-	"strings"
+//	"strings"
 )
 
 type SimpleStore struct {
@@ -50,7 +50,7 @@ func (ctx *SimpleStore) Merge(src ExprContext) {
 		ctx.funcStore[name], _ = src.GetFuncInfo(name)
 	}
 }
-
+/*
 func varsCtxToBuilder(sb *strings.Builder, ctx ExprContext, indent int) {
 	sb.WriteString("vars: {\n")
 	first := true
@@ -77,7 +77,7 @@ func varsCtxToBuilder(sb *strings.Builder, ctx ExprContext, indent int) {
 		}
 	}
 	sb.WriteString(strings.Repeat("\t", indent))
-	sb.WriteString("\n}\n")
+	sb.WriteString("\n}")
 }
 
 func varsCtxToString(ctx ExprContext, indent int) string {
@@ -106,15 +106,59 @@ func funcsCtxToBuilder(sb *strings.Builder, ctx ExprContext, indent int) {
 			sb.WriteString(fmt.Sprintf("%v", value))
 		}
 	}
-	sb.WriteString("\n}\n")
+	sb.WriteString("\n}")
 }
 
 func (ctx *SimpleStore) ToString(opt FmtOpt) string {
 	var sb strings.Builder
 	varsCtxToBuilder(&sb, ctx, 0)
+	sb.WriteByte('\n')
 	funcsCtxToBuilder(&sb, ctx, 0)
 	return sb.String()
 }
+*/
+
+func (ctx *SimpleStore) ToString(opt FmtOpt) string {
+	dict := ctx.ToDict()
+	return dict.ToString(opt)
+}
+
+func (ctx *SimpleStore) varsToDict(dict *DictType) *DictType {
+	names := ctx.EnumVars(nil)
+	slices.Sort(names)
+	for _, name := range ctx.EnumVars(nil) {
+		value, _ := ctx.GetVar(name)
+		if f, ok := value.(Formatter); ok {
+			(*dict)[name] = f.ToString(0)
+		} else if _, ok = value.(Functor); ok {
+			(*dict)[name] = "func(){}"
+		} else {
+			(*dict)[name] = fmt.Sprintf("%v", value)
+		}
+	}
+	return dict
+}
+
+func (ctx *SimpleStore) funcsToDict(dict *DictType) *DictType {
+	names := ctx.EnumFuncs(func(name string) bool { return true })
+	slices.Sort(names)
+	for _, name := range names {
+		value, _ := ctx.GetFuncInfo(name)
+		if formatter, ok := value.(Formatter); ok {
+			(*dict)[name] = formatter.ToString(0)
+		} else {
+			(*dict)[name] = fmt.Sprintf("%v", value)
+		}
+	}
+	return dict
+}
+
+func (ctx *SimpleStore) ToDict() (dict *DictType) {
+	dict = MakeDict()
+	(*dict)["variables"] = ctx.varsToDict(MakeDict())
+	(*dict)["functions"] = ctx.funcsToDict(MakeDict())
+	return
+}
 
 func (ctx *SimpleStore) GetVar(varName string) (v any, exists bool) {
 	v, exists = ctx.varStore[varName]

t_builtin-base_test.go

@@ -1,7 +1,7 @@
 // Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
 // All rights reserved.
 
-// t_func-base_test.go
+// t_builtin-base_test.go
 package expr
 
 import (
@@ -10,7 +10,7 @@ import (
 )
 
 func TestFuncBase(t *testing.T) {
-	section := "Func-Base"
+	section := "Builtin-Base"
 
 	inputs := []inputType{
 		/*   1 */ {`isNil(nil)`, true, nil},

t_builtin-import_test.go

@@ -0,0 +1,24 @@
+// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
+// All rights reserved.
+
+// t_builtin-import_test.go
+package expr
+
+import (
+	"testing"
+)
+
+func TestFuncImport(t *testing.T) {
+	section := "Builtin-Import"
+	inputs := []inputType{
+		/*   1 */ {`builtin "import"; import("./test-resources/test-funcs.expr"); (double(3+a) + 1) * two()`, int64(34), nil},
+		/*   2 */ {`builtin "import"; import("test-funcs.expr"); (double(3+a) + 1) * two()`, int64(34), nil},
+		/*   3 */ {`builtin "import"; importAll("./test-resources/test-funcs.expr"); six()`, int64(6), nil},
+		/*   4 */ {`builtin "import"; import("./test-resources/sample-export-all.expr"); six()`, int64(6), nil},
+	}
+
+	t.Setenv("EXPR_PATH", "test-resources")
+
+	// parserTestSpec(t, section, inputs, 69)
+	parserTest(t, section, inputs)
+}

t_builtin-math-arith_test.go

@@ -1,7 +1,7 @@
 // Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
 // All rights reserved.
 
-// t_func-math-arith_test.go
+// t_builtin-math-arith_test.go
 package expr
 
 import (
@@ -10,7 +10,7 @@ import (
 )
 
 func TestFuncMathArith(t *testing.T) {
-	section := "Func-Math-Arith"
+	section := "Builtin-Math-Arith"
 	inputs := []inputType{
 		/*   1 */ {`builtin "math.arith"; add(1,2)`, int64(3), nil},
 		/*   2 */ {`builtin "math.arith"; add(1,2,3)`, int64(6), nil},

t_builtin-os-file_test.go

@@ -1,7 +1,7 @@
 // Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
 // All rights reserved.
 
-// t_func-os_test.go
+// t_builtin-os-file_test.go
 package expr
 
 import (
@@ -10,7 +10,7 @@ import (
 )
 
 func TestFuncOs(t *testing.T) {
-	section := "Func-OS"
+	section := "Builtin-OS-File"
 	inputs := []inputType{
 		/*   1 */ {`builtin "os.file"`, int64(1), nil},
 		/*   2 */ {`builtin "os.file"; handle=fileOpen("/etc/hosts"); fileClose(handle)`, true, nil},

t_builtin-string_test.go

@@ -0,0 +1,69 @@
+// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
+// All rights reserved.
+
+// t_builtin-string_test.go
+package expr
+
+import (
+	"errors"
+	"testing"
+)
+
+func TestFuncString(t *testing.T) {
+	section := "Builtin-String"
+
+	inputs := []inputType{
+		/*   1 */ {`builtin "string"; strJoin("-", "one", "two", "three")`, "one-two-three", nil},
+		/*   2 */ {`builtin "string"; strJoin("-", ["one", "two", "three"])`, "one-two-three", nil},
+		/*   3 */ {`builtin "string"; ls= ["one", "two", "three"]; strJoin("-", ls)`, "one-two-three", nil},
+		/*   4 */ {`builtin "string"; ls= ["one", "two", "three"]; strJoin(1, ls)`, nil, errors.New(`strJoin(): the "separator" parameter must be a string, got a integer (1)`)},
+		/*   5 */ {`builtin "string"; ls= ["one", 2, "three"]; strJoin("-", ls)`, nil, errors.New(`strJoin(): expected string, got integer (2)`)},
+		/*   6 */ {`builtin "string"; "<"+strTrim("  bye bye  ")+">"`, "<bye bye>", nil},
+		/*   7 */ {`builtin "string"; strSub("0123456789", 1,2)`, "12", nil},
+		/*   8 */ {`builtin "string"; strSub("0123456789", -3,2)`, "78", nil},
+		/*   9 */ {`builtin "string"; strSub("0123456789", -3)`, "789", nil},
+		/*  10 */ {`builtin "string"; strSub("0123456789")`, "0123456789", nil},
+		/*  11 */ {`builtin "string"; strStartsWith("0123456789", "xyz", "012")`, true, nil},
+		/*  12 */ {`builtin "string"; strStartsWith("0123456789", "xyz", "0125")`, false, nil},
+		/*  13 */ {`builtin "string"; strStartsWith("0123456789")`, nil, errors.New(`strStartsWith(): too few params -- expected 2 or more, got 1`)},
+		/*  14 */ {`builtin "string"; strEndsWith("0123456789", "xyz", "789")`, true, nil},
+		/*  15 */ {`builtin "string"; strEndsWith("0123456789", "xyz", "0125")`, false, nil},
+		/*  16 */ {`builtin "string"; strEndsWith("0123456789")`, nil, errors.New(`strEndsWith(): too few params -- expected 2 or more, got 1`)},
+		/*  17 */ {`builtin "string"; strSplit("one-two-three", "-")`, newListA("one", "two", "three"), nil},
+		/*  18 */ {`builtin "string"; strJoin("-", [1, "two", "three"])`, nil, errors.New(`strJoin(): expected string, got integer (1)`)},
+		/*  19 */ {`builtin "string"; strJoin()`, nil, errors.New(`strJoin(): too few params -- expected 1 or more, got 0`)},
+
+		/*  69 */ /*{`builtin "string"; $$global`, `vars: {
+		}
+		funcs: {
+		    	add(any=0 ...) -> number,
+		    	dec(any) -> decimal,
+		    	endsWithStr(source, suffix) -> boolean,
+		    	fract(any, denominator=1) -> fraction,
+		    	import( ...) -> any,
+		    	importAll( ...) -> any,
+		    	int(any) -> integer,
+		    	isBool(any) -> boolean,
+		    	isDec(any) -> boolean,
+		    	isDict(any) -> boolean,
+		    	isFloat(any) -> boolean,
+		    	isFract(any) -> boolean,
+		    	isInt(any) -> boolean,
+		    	isList(any) -> boolean,
+		    	isNil(any) -> boolean,
+		    	isString(any) -> boolean,
+		    	joinStr(separator, item="" ...) -> string,
+		    	mul(any=1 ...) -> number,
+		    	splitStr(source, separator="", count=-1) -> list of string,
+		    	startsWithStr(source, prefix) -> boolean,
+		    	subStr(source, start=0, count=-1) -> string,
+		    	trimStr(source) -> string
+		}
+		`, nil},*/
+	}
+
+	//t.Setenv("EXPR_PATH", ".")
+
+	// parserTestSpec(t, section, inputs, 19)
+	parserTest(t, section, inputs)
+}

t_func-import_test.go

@@ -1,24 +0,0 @@
-// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
-// All rights reserved.
-
-// t_func-import_test.go
-package expr
-
-import (
-	"testing"
-)
-
-func TestFuncImport(t *testing.T) {
-	section := "Func-Import"
-	inputs := []inputType{
-		/*   1 */ {`builtin "import"; import("./test-funcs.expr"); (double(3+a) + 1) * two()`, int64(34), nil},
-		/*   2 */ {`builtin "import"; import("test-funcs.expr"); (double(3+a) + 1) * two()`, int64(34), nil},
-		/*   3 */ {`builtin "import"; importAll("./test-funcs.expr"); six()`, int64(6), nil},
-		/*   4 */ {`builtin "import"; import("./sample-export-all.expr"); six()`, int64(6), nil},
-	}
-
-	t.Setenv("EXPR_PATH", ".")
-
-	// parserTestSpec(t, section, inputs, 69)
-	parserTest(t, section, inputs)
-}

t_func-string_test.go

@@ -1,69 +0,0 @@
-// Copyright (c) 2024 Celestino Amoroso (celestino.amoroso@gmail.com).
-// All rights reserved.
-
-// t_func-string_test.go
-package expr
-
-import (
-	"errors"
-	"testing"
-)
-
-func TestFuncString(t *testing.T) {
-	section := "Func-String"
-
-	inputs := []inputType{
-		/*   1 */ {`builtin "string"; joinStr("-", "one", "two", "three")`, "one-two-three", nil},
-		/*   2 */ {`builtin "string"; joinStr("-", ["one", "two", "three"])`, "one-two-three", nil},
-		/*   3 */ {`builtin "string"; ls= ["one", "two", "three"]; joinStr("-", ls)`, "one-two-three", nil},
-		/*   4 */ {`builtin "string"; ls= ["one", "two", "three"]; joinStr(1, ls)`, nil, errors.New(`joinStr() the "separator" parameter must be a string, got a integer (1)`)},
-		/*   5 */ {`builtin "string"; ls= ["one", 2, "three"]; joinStr("-", ls)`, nil, errors.New(`joinStr() expected string, got integer (2)`)},
-		/*   6 */ {`builtin "string"; "<"+trimStr("  bye bye  ")+">"`, "<bye bye>", nil},
-		/*   7 */ {`builtin "string"; subStr("0123456789", 1,2)`, "12", nil},
-		/*   8 */ {`builtin "string"; subStr("0123456789", -3,2)`, "78", nil},
-		/*   9 */ {`builtin "string"; subStr("0123456789", -3)`, "789", nil},
-		/*  10 */ {`builtin "string"; subStr("0123456789")`, "0123456789", nil},
-		/*  11 */ {`builtin "string"; startsWithStr("0123456789", "xyz", "012")`, true, nil},
-		/*  12 */ {`builtin "string"; startsWithStr("0123456789", "xyz", "0125")`, false, nil},
-		/*  13 */ {`builtin "string"; startsWithStr("0123456789")`, nil, errors.New(`startsWithStr(): too few params -- expected 2 or more, got 1`)},
-		/*  14 */ {`builtin "string"; endsWithStr("0123456789", "xyz", "789")`, true, nil},
-		/*  15 */ {`builtin "string"; endsWithStr("0123456789", "xyz", "0125")`, false, nil},
-		/*  16 */ {`builtin "string"; endsWithStr("0123456789")`, nil, errors.New(`endsWithStr(): too few params -- expected 2 or more, got 1`)},
-		/*  17 */ {`builtin "string"; splitStr("one-two-three", "-")`, newListA("one", "two", "three"), nil},
-		/*  18 */ {`builtin "string"; joinStr("-", [1, "two", "three"])`, nil, errors.New(`joinStr() expected string, got integer (1)`)},
-		/*  19 */ {`builtin "string"; joinStr()`, nil, errors.New(`joinStr(): too few params -- expected 1 or more, got 0`)},
-
-		/*  69 */ /*{`builtin "string"; $$global`, `vars: {
-		}
-		funcs: {
-		    	add(any=0 ...) -> number,
-		    	dec(any) -> decimal,
-		    	endsWithStr(source, suffix) -> boolean,
-		    	fract(any, denominator=1) -> fraction,
-		    	import( ...) -> any,
-		    	importAll( ...) -> any,
-		    	int(any) -> integer,
-		    	isBool(any) -> boolean,
-		    	isDec(any) -> boolean,
-		    	isDict(any) -> boolean,
-		    	isFloat(any) -> boolean,
-		    	isFract(any) -> boolean,
-		    	isInt(any) -> boolean,
-		    	isList(any) -> boolean,
-		    	isNil(any) -> boolean,
-		    	isString(any) -> boolean,
-		    	joinStr(separator, item="" ...) -> string,
-		    	mul(any=1 ...) -> number,
-		    	splitStr(source, separator="", count=-1) -> list of string,
-		    	startsWithStr(source, prefix) -> boolean,
-		    	subStr(source, start=0, count=-1) -> string,
-		    	trimStr(source) -> string
-		}
-		`, nil},*/
-	}
-
-	//t.Setenv("EXPR_PATH", ".")
-
-	// parserTestSpec(t, section, inputs, 19)
-	parserTest(t, section, inputs)
-}

t_funcs_test.go

@@ -44,7 +44,7 @@ func dummy(ctx ExprContext, name string, args []any) (result any, err error) {
 
 func TestFunctionToStringSimple(t *testing.T) {
 	source := NewGolangFunctor(dummy)
-	want := "func() {<body>}"
+	want := "func() {}"
 	got := source.ToString(0)
 	if got != want {
 		t.Errorf(`(func() -> result = %v [%T], want = %v [%T]`, got, got, want, want)

t_scanner_test.go

@@ -45,7 +45,7 @@ func TestScanner(t *testing.T) {
 		/* 22 */ {"@", SymAt, nil, nil},
 		/* 23 */ {`#`, SymHash, nil, nil},
 		/* 24 */ {`%`, SymPercent, nil, nil},
-		/* 25 */ {`'`, SymQuote, nil, nil},
+		/* 25 */ {`\'`, SymQuote, nil, nil},
 		/* 26 */ {`\"`, SymDoubleQuote, nil, nil},
 		/* 27 */ {`_`, SymUndescore, nil, nil},
 		/* 28 */ {`<>`, SymLessGreater, nil, nil},

t_utils_test.go

@@ -63,7 +63,7 @@ func TestIsString(t *testing.T) {
 	}
 
 	count++
-	b, ok := toBool(true)
+	b, ok := ToBool(true)
 	if !(ok && b) {
 		t.Errorf("%d: toBool(true) b=%v, ok=%v -> result = false, want true", count, b, ok)
 		failed++
@@ -72,7 +72,7 @@ func TestIsString(t *testing.T) {
 	}
 
 	count++
-	b, ok = toBool("abc")
+	b, ok = ToBool("abc")
 	if !(ok && b) {
 		t.Errorf("%d: toBool(\"abc\") b=%v, ok=%v -> result = false, want true", count, b, ok)
 		failed++
@@ -81,7 +81,7 @@ func TestIsString(t *testing.T) {
 	}
 
 	count++
-	b, ok = toBool([]int{})
+	b, ok = ToBool([]int{})
 	if ok {
 		t.Errorf("%d: toBool([]) b=%v, ok=%v -> result = true, want false", count, b, ok)
 		failed++
@@ -97,7 +97,7 @@ func TestToIntOk(t *testing.T) {
 	wantValue := int(64)
 	wantErr := error(nil)
 
-	gotValue, gotErr := toInt(source, "test")
+	gotValue, gotErr := ToInt(source, "test")
 
 	if gotErr != nil || gotValue != wantValue {
 		t.Errorf("toInt(%v, \"test\") gotValue=%v, gotErr=%v -> wantValue=%v, wantErr=%v",
@@ -110,7 +110,7 @@ func TestToIntErr(t *testing.T) {
 	wantValue := 0
 	wantErr := errors.New(`test expected integer, got uint64 (64)`)
 
-	gotValue, gotErr := toInt(source, "test")
+	gotValue, gotErr := ToInt(source, "test")
 
 	if gotErr.Error() != wantErr.Error() || gotValue != wantValue {
 		t.Errorf("toInt(%v, \"test\") gotValue=%v, gotErr=%v -> wantValue=%v, wantErr=%v",

utils.go

@@ -86,7 +86,7 @@ func numAsFloat(v any) (f float64) {
 	return
 }
 
-func toBool(v any) (b bool, ok bool) {
+func ToBool(v any) (b bool, ok bool) {
 	ok = true
 	switch x := v.(type) {
 	case string:
@@ -201,7 +201,7 @@ func CloneFilteredMap[K comparable, V any](source map[K]V, filter func(key K) (a
 	return CopyFilteredMap(dest, source, filter)
 }
 
-func toInt(value any, description string) (i int, err error) {
+func ToInt(value any, description string) (i int, err error) {
 	if valueInt64, ok := value.(int64); ok {
 		i = int(valueInt64)
 	} else if valueInt, ok := value.(int); ok {