self param replaced as opTerm

operand-dict.go

@@ -18,8 +18,8 @@ func newDictTerm(args map[any]*term) *term {
 }
 
 // -------- dict func
-func evalDict(ctx ExprContext, self *term) (v any, err error) {
+func evalDict(ctx ExprContext, opTerm *term) (v any, err error) {
-	dict, _ := self.value().(map[any]*term)
+	dict, _ := opTerm.value().(map[any]*term)
 	items := make(DictType, len(dict))
 	for key, tree := range dict {
 		var param any

operand-expr.go

@@ -20,11 +20,11 @@ func newExprTerm(root *term) *term {
 }
 
 // -------- eval expr
-func evalExpr(ctx ExprContext, self *term) (v any, err error) {
+func evalExpr(ctx ExprContext, opTerm *term) (v any, err error) {
-	if expr, ok := self.value().(*term); ok {
+	if expr, ok := opTerm.value().(*term); ok {
 		v, err = expr.compute(ctx)
 	} else {
-		err = fmt.Errorf("expression expected, got %T", self.value())
+		err = fmt.Errorf("expression expected, got %T", opTerm.value())
 	}
 	return
 }

operand-func.go

@@ -21,10 +21,10 @@ func newFuncCallTerm(tk *Token, args []*term) *term {
 }
 
 // -------- eval func call
-func evalFuncCall(ctx ExprContext, self *term) (v any, err error) {
+func evalFuncCall(ctx ExprContext, opTerm *term) (v any, err error) {
-	name, _ := self.tk.Value.(string)
+	name, _ := opTerm.tk.Value.(string)
-	params := make([]any, len(self.children), len(self.children)+5)
+	params := make([]any, len(opTerm.children), len(opTerm.children)+5)
-	for i, tree := range self.children {
+	for i, tree := range opTerm.children {
 		var param any
 		if param, err = tree.compute(ctx); err != nil {
 			break
@@ -51,11 +51,11 @@ func newFuncDefTerm(tk *Token, args []*term) *term {
 }
 
 // -------- eval func def
-func evalFuncDef(ctx ExprContext, self *term) (v any, err error) {
+func evalFuncDef(ctx ExprContext, opTerm *term) (v any, err error) {
-	bodySpec := self.value()
+	bodySpec := opTerm.value()
 	if expr, ok := bodySpec.(*ast); ok {
-		paramList := make([]ExprFuncParam, 0, len(self.children))
+		paramList := make([]ExprFuncParam, 0, len(opTerm.children))
-		for _, param := range self.children {
+		for _, param := range opTerm.children {
 			var defValue any
 			flags := paramFlags(0)
 			if len(param.children) > 0 {

operand-iterator.go

@@ -95,15 +95,15 @@ func getDataSourceDict(iteratorTerm *term, firstChildValue any) (ds map[string]F
 	return
 }
 
-func evalIterator(ctx ExprContext, iteratorTerm *term) (v any, err error) {
+func evalIterator(ctx ExprContext, opTerm *term) (v any, err error) {
 	var firstChildValue any
 	var ds map[string]Functor
 
-	if firstChildValue, err = evalFirstChild(ctx, iteratorTerm); err != nil {
+	if firstChildValue, err = evalFirstChild(ctx, opTerm); err != nil {
 		return
 	}
 
-	if ds, err = getDataSourceDict(iteratorTerm, firstChildValue); err != nil {
+	if ds, err = getDataSourceDict(opTerm, firstChildValue); err != nil {
 		return
 	}
 
@@ -111,8 +111,8 @@ func evalIterator(ctx ExprContext, iteratorTerm *term) (v any, err error) {
 		dc := newDataCursor(ctx, ds)
 		if initFunc, exists := ds[initName]; exists && initFunc != nil {
 			var args []any
-			if len(iteratorTerm.children) > 1 {
+			if len(opTerm.children) > 1 {
-				if args, err = evalTermArray(ctx, iteratorTerm.children[1:]); err != nil {
+				if args, err = evalTermArray(ctx, opTerm.children[1:]); err != nil {
 					return
 				}
 			} else {
@@ -134,12 +134,12 @@ func evalIterator(ctx ExprContext, iteratorTerm *term) (v any, err error) {
 		v = dc
 	} else if list, ok := firstChildValue.(*ListType); ok {
 		var args []any
-		if args, err = evalSibling(ctx, iteratorTerm.children, nil); err == nil {
+		if args, err = evalSibling(ctx, opTerm.children, nil); err == nil {
 			v = NewListIterator(list, args)
 		}
 	} else {
 		var list []any
-		if list, err = evalSibling(ctx, iteratorTerm.children, firstChildValue); err == nil {
+		if list, err = evalSibling(ctx, opTerm.children, firstChildValue); err == nil {
 			v = NewArrayIterator(list)
 		}
 	}

operand-list.go

@@ -21,8 +21,8 @@ func newListTerm(row, col int, args []*term) *term {
 }
 
 // -------- list func
-func evalList(ctx ExprContext, self *term) (v any, err error) {
+func evalList(ctx ExprContext, opTerm *term) (v any, err error) {
-	list, _ := self.value().([]*term)
+	list, _ := opTerm.value().([]*term)
 	items := make(ListType, len(list))
 	for i, tree := range list {
 		var param any

operand-literal.go

@@ -17,8 +17,8 @@ func newLiteralTerm(tk *Token) *term {
 }
 
 // -------- eval func
-func evalLiteral(ctx ExprContext, self *term) (v any, err error) {
+func evalLiteral(ctx ExprContext, opTerm *term) (v any, err error) {
-	v = self.tk.Value
+	v = opTerm.tk.Value
 	return
 }
 

operand-selector-case.go

@@ -41,10 +41,10 @@ func newSelectorCaseTerm(row, col int, filterList *term, caseExpr Expr) *term {
 }
 
 // -------- eval selector case
-func evalSelectorCase(ctx ExprContext, self *term) (v any, err error) {
+func evalSelectorCase(ctx ExprContext, opTerm *term) (v any, err error) {
 	var ok bool
-	if v, ok = self.value().(*selectorCase); !ok {
+	if v, ok = opTerm.value().(*selectorCase); !ok {
-		err = fmt.Errorf("selector-case expected, got %T", self.value())
+		err = fmt.Errorf("selector-case expected, got %T", opTerm.value())
 	}
 	return
 }

operand-var.go

@@ -21,9 +21,9 @@ func newVarTerm(tk *Token) *term {
 }
 
 // -------- eval func
-func evalVar(ctx ExprContext, self *term) (v any, err error) {
+func evalVar(ctx ExprContext, opTerm *term) (v any, err error) {
 	var exists bool
-	name := self.source()
+	name := opTerm.source()
 	if v, exists = GetVar(ctx, name); !exists {
 		if info, exists, _ := GetFuncInfo(ctx, name); exists {
 			v = info.Functor()

operator-assign.go

@@ -60,19 +60,19 @@ func assignValue(ctx ExprContext, leftTerm *term, v any) (err error) {
 	return
 }
 
-func evalAssign(ctx ExprContext, self *term) (v any, err error) {
+func evalAssign(ctx ExprContext, opTerm *term) (v any, err error) {
-	if err = self.checkOperands(); err != nil {
+	if err = opTerm.checkOperands(); err != nil {
 		return
 	}
 
-	leftTerm := self.children[0]
+	leftTerm := opTerm.children[0]
 	leftSym := leftTerm.symbol()
 	if leftSym != SymVariable && leftSym != SymIndex {
-		err = leftTerm.tk.Errorf("left operand of %q must be a variable or a collection's item", self.tk.source)
+		err = leftTerm.tk.Errorf("left operand of %q must be a variable or a collection's item", opTerm.tk.source)
 		return
 	}
 
-	rightChild := self.children[1]
+	rightChild := opTerm.children[1]
 
 	if v, err = rightChild.compute(ctx); err == nil {
 		if functor, ok := v.(Functor); ok {
@@ -83,7 +83,7 @@ func evalAssign(ctx ExprContext, self *term) (v any, err error) {
 
 				ctx.RegisterFunc(leftTerm.source(), functor, TypeAny, paramSpecs)
 			} else {
-				err = self.Errorf("unknown function %s()", rightChild.source())
+				err = opTerm.Errorf("unknown function %s()", rightChild.source())
 			}
 		} else {
 			err = assignValue(ctx, leftTerm, v)

operator-bool.go

@@ -18,17 +18,17 @@ func newNotTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalNot(ctx ExprContext, self *term) (v any, err error) {
+func evalNot(ctx ExprContext, opTerm *term) (v any, err error) {
 	var rightValue any
 
-	if rightValue, err = self.evalPrefix(ctx); err != nil {
+	if rightValue, err = opTerm.evalPrefix(ctx); err != nil {
 		return
 	}
 
 	if b, ok := ToBool(rightValue); ok {
 		v = !b
 	} else {
-		err = self.errIncompatibleType(rightValue)
+		err = opTerm.errIncompatibleType(rightValue)
 	}
 	return
 }

operator-builtin.go

@@ -18,10 +18,10 @@ func newBuiltinTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalBuiltin(ctx ExprContext, self *term) (v any, err error) {
+func evalBuiltin(ctx ExprContext, opTerm *term) (v any, err error) {
 	var childValue any
 
-	if childValue, err = self.evalPrefix(ctx); err != nil {
+	if childValue, err = opTerm.evalPrefix(ctx); err != nil {
 		return
 	}
 
@@ -37,11 +37,11 @@ func evalBuiltin(ctx ExprContext, self *term) (v any, err error) {
 				if ImportInContext(module) {
 					count++
 				} else {
-					err = self.Errorf("unknown builtin module %q", module)
+					err = opTerm.Errorf("unknown builtin module %q", module)
 					break
 				}
 			} else {
-				err = self.Errorf("expected string at item nr %d, got %s", it.Index()+1, TypeName(moduleSpec))
+				err = opTerm.Errorf("expected string at item nr %d, got %s", it.Index()+1, TypeName(moduleSpec))
 				break
 			}
 		}

operator-but.go

@@ -16,8 +16,8 @@ func newButTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalBut(ctx ExprContext, self *term) (v any, err error) {
+func evalBut(ctx ExprContext, opTerm *term) (v any, err error) {
-	_, v, err = self.evalInfix(ctx)
+	_, v, err = opTerm.evalInfix(ctx)
 	return
 }
 

operator-context.go

@@ -16,15 +16,15 @@ func newContextTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalContextValue(ctx ExprContext, self *term) (v any, err error) {
+func evalContextValue(ctx ExprContext, opTerm *term) (v any, err error) {
 	var childValue any
 
 	var sourceCtx ExprContext
-	if self.children == nil || len(self.children) == 0 {
+	if opTerm.children == nil || len(opTerm.children) == 0 {
 		sourceCtx = ctx
-	} else if self.children[0].symbol() == SymVariable && self.children[0].source() == "global" {
+	} else if opTerm.children[0].symbol() == SymVariable && opTerm.children[0].source() == "global" {
 		sourceCtx = globalCtx
-	} else if childValue, err = self.evalPrefix(ctx); err == nil {
+	} else if childValue, err = opTerm.evalPrefix(ctx); err == nil {
 		if dc, ok := childValue.(*dataCursor); ok {
 			sourceCtx = dc.ctx
 		}
@@ -49,7 +49,7 @@ func evalContextValue(ctx ExprContext, self *term) (v any, err error) {
 			v = d
 		}
 	} else {
-		err = self.errIncompatibleType(childValue)
+		err = opTerm.errIncompatibleType(childValue)
 	}
 	return
 }

operator-ctrl.go

@@ -16,7 +16,7 @@ func newExportAllTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalExportAll(ctx ExprContext, self *term) (v any, err error) {
+func evalExportAll(ctx ExprContext, opTerm *term) (v any, err error) {
 	CtrlEnable(ctx, control_export_all)
 	return
 }

operator-default.go

@@ -16,23 +16,23 @@ func newDefaultTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalDefault(ctx ExprContext, self *term) (v any, err error) {
+func evalDefault(ctx ExprContext, opTerm *term) (v any, err error) {
 	var rightValue any
 
-	if err = self.checkOperands(); err != nil {
+	if err = opTerm.checkOperands(); err != nil {
 		return
 	}
 
-	leftTerm := self.children[0]
+	leftTerm := opTerm.children[0]
 	if leftTerm.tk.Sym != SymVariable {
 		// err = leftTerm.Errorf("left operand of %q must be a variable", self.tk.source)
-		err = ErrLeftOperandMustBeVariable(leftTerm, self)
+		err = ErrLeftOperandMustBeVariable(leftTerm, opTerm)
 		return
 	}
 
 	if leftValue, exists := ctx.GetVar(leftTerm.source()); exists {
 		v = leftValue
-	} else if rightValue, err = self.children[1].compute(ctx); err == nil {
+	} else if rightValue, err = opTerm.children[1].compute(ctx); err == nil {
 		v = rightValue
 	}
 	return
@@ -50,22 +50,22 @@ func newAlternateTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalAlternate(ctx ExprContext, self *term) (v any, err error) {
+func evalAlternate(ctx ExprContext, opTerm *term) (v any, err error) {
 	var rightValue any
 
-	if err = self.checkOperands(); err != nil {
+	if err = opTerm.checkOperands(); err != nil {
 		return
 	}
 
-	leftTerm := self.children[0]
+	leftTerm := opTerm.children[0]
 	if leftTerm.tk.Sym != SymVariable {
 		// err = leftTerm.Errorf("left operand of %q must be a variable", self.tk.source)
-		err = ErrLeftOperandMustBeVariable(leftTerm, self)
+		err = ErrLeftOperandMustBeVariable(leftTerm, opTerm)
 		return
 	}
 
 	if leftValue, exists := ctx.GetVar(leftTerm.source()); exists && leftValue != nil {
-		if rightValue, err = self.children[1].compute(ctx); err == nil {
+		if rightValue, err = opTerm.children[1].compute(ctx); err == nil {
 			v = rightValue
 		}
 	} else {
@@ -86,23 +86,23 @@ func newDefaultAssignTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalAssignDefault(ctx ExprContext, self *term) (v any, err error) {
+func evalAssignDefault(ctx ExprContext, opTerm *term) (v any, err error) {
 	var rightValue any
 
-	if err = self.checkOperands(); err != nil {
+	if err = opTerm.checkOperands(); err != nil {
 		return
 	}
 
-	leftTerm := self.children[0]
+	leftTerm := opTerm.children[0]
 	if leftTerm.tk.Sym != SymVariable {
 		// err = leftTerm.Errorf("left operand of %q must be a variable", self.tk.source)
-		err = ErrLeftOperandMustBeVariable(leftTerm, self)
+		err = ErrLeftOperandMustBeVariable(leftTerm, opTerm)
 		return
 	}
 
 	if leftValue, exists := ctx.GetVar(leftTerm.source()); exists {
 		v = leftValue
-	} else if rightValue, err = self.children[1].compute(ctx); err == nil {
+	} else if rightValue, err = opTerm.children[1].compute(ctx); err == nil {
 		if functor, ok := rightValue.(Functor); ok {
 			//ctx.RegisterFunc(leftTerm.source(), functor, 0, -1)
 			ctx.RegisterFunc(leftTerm.source(), functor, TypeAny, []ExprFuncParam{

operator-dot.go

@@ -15,17 +15,17 @@ func newDotTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalDot(ctx ExprContext, self *term) (v any, err error) {
+func evalDot(ctx ExprContext, opTerm *term) (v any, err error) {
 	var leftValue, rightValue any
 
-	if err = self.checkOperands(); err != nil {
+	if err = opTerm.checkOperands(); err != nil {
 		return
 	}
-	if leftValue, err = self.children[0].compute(ctx); err != nil {
+	if leftValue, err = opTerm.children[0].compute(ctx); err != nil {
 		return
 	}
 
-	indexTerm := self.children[1]
+	indexTerm := opTerm.children[1]
 
 	switch unboxedValue := leftValue.(type) {
 	case ExtIterator:
@@ -41,8 +41,8 @@ func evalDot(ctx ExprContext, self *term) (v any, err error) {
 			err = indexTerm.tk.ErrorExpectedGot("identifier")
 		}
 	default:
-		if rightValue, err = self.children[1].compute(ctx); err == nil {
+		if rightValue, err = opTerm.children[1].compute(ctx); err == nil {
-			err = self.errIncompatibleTypes(leftValue, rightValue)
+			err = opTerm.errIncompatibleTypes(leftValue, rightValue)
 		}
 	}
 	return

operator-fact.go

@@ -18,10 +18,10 @@ func newFactTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalFact(ctx ExprContext, self *term) (v any, err error) {
+func evalFact(ctx ExprContext, opTerm *term) (v any, err error) {
 	var leftValue any
 
-	if leftValue, err = self.evalPrefix(ctx); err != nil {
+	if leftValue, err = opTerm.evalPrefix(ctx); err != nil {
 		return
 	}
 
@@ -36,7 +36,7 @@ func evalFact(ctx ExprContext, self *term) (v any, err error) {
 			err = fmt.Errorf("factorial of a negative integer (%d) is not allowed", i)
 		}
 	} else {
-		err = self.errIncompatibleType(leftValue)
+		err = opTerm.errIncompatibleType(leftValue)
 	}
 	return
 }

operator-fraction.go

@@ -24,12 +24,12 @@ func newFractionTerm(tk *Token) *term {
 }
 
 // -------- eval func
-func evalFraction(ctx ExprContext, self *term) (v any, err error) {
+func evalFraction(ctx ExprContext, opTerm *term) (v any, err error) {
 	var numValue, denValue any
 	var num, den int64
 	var ok bool
 
-	if numValue, denValue, err = self.evalInfix(ctx); err != nil {
+	if numValue, denValue, err = opTerm.evalInfix(ctx); err != nil {
 		return
 	}
 	if num, ok = numValue.(int64); !ok {

operator-in.go

@@ -21,10 +21,10 @@ func newInTerm(tk *Token) (inst *term) {
 // 	return
 // }
 
-func evalIn(ctx ExprContext, self *term) (v any, err error) {
+func evalIn(ctx ExprContext, opTerm *term) (v any, err error) {
 	var leftValue, rightValue any
 
-	if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
+	if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
 		return
 	}
 
@@ -35,7 +35,7 @@ func evalIn(ctx ExprContext, self *term) (v any, err error) {
 		dict, _ := rightValue.(*DictType)
 		v = dict.hasKey(leftValue)
 	} else {
-		err = self.errIncompatibleTypes(leftValue, rightValue)
+		err = opTerm.errIncompatibleTypes(leftValue, rightValue)
 	}
 	return
 }

operator-include.go

@@ -16,10 +16,10 @@ func newIncludeTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalInclude(ctx ExprContext, self *term) (v any, err error) {
+func evalInclude(ctx ExprContext, opTerm *term) (v any, err error) {
 	var childValue any
 
-	if childValue, err = self.evalPrefix(ctx); err != nil {
+	if childValue, err = opTerm.evalPrefix(ctx); err != nil {
 		return
 	}
 
@@ -31,11 +31,11 @@ func evalInclude(ctx ExprContext, self *term) (v any, err error) {
 				if v, err = EvalFile(ctx, filePath); err == nil {
 					count++
 				} else {
-					err = self.Errorf("can't load file %q", filePath)
+					err = opTerm.Errorf("can't load file %q", filePath)
 					break
 				}
 			} else {
-				err = self.Errorf("expected string at item nr %d, got %T", i+1, filePathSpec)
+				err = opTerm.Errorf("expected string at item nr %d, got %T", i+1, filePathSpec)
 				break
 			}
 		}
@@ -45,7 +45,7 @@ func evalInclude(ctx ExprContext, self *term) (v any, err error) {
 			count++
 		}
 	} else {
-		err = self.errIncompatibleType(childValue)
+		err = opTerm.errIncompatibleType(childValue)
 	}
 	if err == nil {
 		v = count

operator-index.go

@@ -59,18 +59,18 @@ func verifyRange(indexTerm *term, indexList *ListType, maxValue int) (startIndex
 	return
 }
 
-func evalIndex(ctx ExprContext, self *term) (v any, err error) {
+func evalIndex(ctx ExprContext, opTerm *term) (v any, err error) {
 	var leftValue, rightValue any
 	var indexList *ListType
 	var ok bool
 
-	if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
+	if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
 		return
 	}
 
-	indexTerm := self.children[1]
+	indexTerm := opTerm.children[1]
 	if indexList, ok = rightValue.(*ListType); !ok {
-		err = self.Errorf("invalid index expression")
+		err = opTerm.Errorf("invalid index expression")
 		return
 	} else if len(*indexList) != 1 {
 		err = indexTerm.Errorf("one index only is allowed")
@@ -90,16 +90,9 @@ func evalIndex(ctx ExprContext, self *term) (v any, err error) {
 				v = string(unboxedValue[index])
 			}
 		case *DictType:
-/* 			var ok bool
-			var indexValue any
-			if indexValue, err = verifyKey(indexTerm, indexList); err == nil {
-				if v, ok = (*unboxedValue)[indexValue]; !ok {
-					err = indexTerm.Errorf("key %v does not belong to the dictionary", rightValue)
-				}
-			} */
 			v, err = getDictItem(unboxedValue, indexTerm, indexList, rightValue)
 		default:
-			err = self.errIncompatibleTypes(leftValue, rightValue)
+			err = opTerm.errIncompatibleTypes(leftValue, rightValue)
 		}
 	} else if isIntPair((*indexList)[0]) {
 		switch unboxedValue := leftValue.(type) {
@@ -115,18 +108,10 @@ func evalIndex(ctx ExprContext, self *term) (v any, err error) {
 				v = unboxedValue[start:end]
 			}
 		default:
-			err = self.errIncompatibleTypes(leftValue, rightValue)
+			err = opTerm.errIncompatibleTypes(leftValue, rightValue)
 		}
 	} else if IsDict(leftValue) {
 		d := leftValue.(*DictType)
-
-		/* 		var ok bool
-		   		var indexValue any
-		   		if indexValue, err = verifyKey(indexTerm, indexList); err == nil {
-		   			if v, ok = (*d)[indexValue]; !ok {
-		   				err = indexTerm.Errorf("key %v does not belong to the dictionary", rightValue)
-		   			}
-		   		}*/
 		v, err = getDictItem(d, indexTerm, indexList, rightValue)
 	}
 	return

operator-insert.go

@@ -26,10 +26,10 @@ func newAppendTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalInsert(ctx ExprContext, self *term) (v any, err error) {
+func evalInsert(ctx ExprContext, opTerm *term) (v any, err error) {
 	var leftValue, rightValue any
 
-	if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
+	if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
 		return
 	}
 
@@ -37,19 +37,19 @@ func evalInsert(ctx ExprContext, self *term) (v any, err error) {
 		list, _ := rightValue.(*ListType)
 		newList := append(ListType{leftValue}, *list...)
 		v = &newList
-		if self.children[1].symbol() == SymVariable {
+		if opTerm.children[1].symbol() == SymVariable {
-			ctx.UnsafeSetVar(self.children[1].source(), v)
+			ctx.UnsafeSetVar(opTerm.children[1].source(), v)
 		}
 	} else {
-		err = self.errIncompatibleTypes(leftValue, rightValue)
+		err = opTerm.errIncompatibleTypes(leftValue, rightValue)
 	}
 	return
 }
 
-func evalAppend(ctx ExprContext, self *term) (v any, err error) {
+func evalAppend(ctx ExprContext, opTerm *term) (v any, err error) {
 	var leftValue, rightValue any
 
-	if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
+	if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
 		return
 	}
 
@@ -57,11 +57,11 @@ func evalAppend(ctx ExprContext, self *term) (v any, err error) {
 		list, _ := leftValue.(*ListType)
 		newList := append(*list, rightValue)
 		v = &newList
-		if self.children[0].symbol() == SymVariable {
+		if opTerm.children[0].symbol() == SymVariable {
-			ctx.UnsafeSetVar(self.children[0].source(), v)
+			ctx.UnsafeSetVar(opTerm.children[0].source(), v)
 		}
 	} else {
-		err = self.errIncompatibleTypes(leftValue, rightValue)
+		err = opTerm.errIncompatibleTypes(leftValue, rightValue)
 	}
 	return
 }

operator-iter-value.go

@@ -16,17 +16,17 @@ func newIterValueTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalIterValue(ctx ExprContext, self *term) (v any, err error) {
+func evalIterValue(ctx ExprContext, opTerm *term) (v any, err error) {
 	var childValue any
 
-	if childValue, err = self.evalPrefix(ctx); err != nil {
+	if childValue, err = opTerm.evalPrefix(ctx); err != nil {
 		return
 	}
 
 	if it, ok := childValue.(Iterator); ok {
 		v, err = it.Current()
 	} else {
-		err = self.errIncompatibleType(childValue)
+		err = opTerm.errIncompatibleType(childValue)
 	}
 	return
 }

operator-length.go

@@ -16,10 +16,10 @@ func newLengthTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalLength(ctx ExprContext, self *term) (v any, err error) {
+func evalLength(ctx ExprContext, opTerm *term) (v any, err error) {
 	var childValue any
 
-	if childValue, err = self.evalPrefix(ctx); err != nil {
+	if childValue, err = opTerm.evalPrefix(ctx); err != nil {
 		return
 	}
 
@@ -41,7 +41,7 @@ func evalLength(ctx ExprContext, self *term) (v any, err error) {
 			v = int64(it.Index() + 1)
 		}
 	} else {
-		err = self.errIncompatibleType(childValue)
+		err = opTerm.errIncompatibleType(childValue)
 	}
 	return
 }

operator-plugin.go

@@ -20,11 +20,11 @@ func newPluginTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalPlugin(ctx ExprContext, self *term) (v any, err error) {
+func evalPlugin(ctx ExprContext, opTerm *term) (v any, err error) {
 	var childValue any
 	var moduleSpec any
 
-	if childValue, err = self.evalPrefix(ctx); err != nil {
+	if childValue, err = opTerm.evalPrefix(ctx); err != nil {
 		return
 	}
 
@@ -38,7 +38,7 @@ func evalPlugin(ctx ExprContext, self *term) (v any, err error) {
 			}
 			count++
 		} else {
-			err = self.Errorf("expected string as item nr %d, got %s", it.Index()+1, TypeName(moduleSpec))
+			err = opTerm.Errorf("expected string as item nr %d, got %s", it.Index()+1, TypeName(moduleSpec))
 			break
 		}
 	}

operator-post-inc.go

@@ -17,20 +17,20 @@ func newPostIncTerm(tk *Token) *term {
 	}
 }
 
-func evalPostInc(ctx ExprContext, self *term) (v any, err error) {
+func evalPostInc(ctx ExprContext, opTerm *term) (v any, err error) {
 	var childValue any
-	if childValue, err = self.evalPrefix(ctx); err != nil {
+	if childValue, err = opTerm.evalPrefix(ctx); err != nil {
 		return
 	}
 
 	if it, ok := childValue.(Iterator); ok {
 		v, err = it.Next()
-	} else if IsInteger(childValue) && self.children[0].symbol() == SymVariable {
+	} else if IsInteger(childValue) && opTerm.children[0].symbol() == SymVariable {
 		v = childValue
 		i, _ := childValue.(int64)
-		ctx.SetVar(self.children[0].source(), i+1)
+		ctx.SetVar(opTerm.children[0].source(), i+1)
 	} else {
-		err = self.errIncompatibleType(childValue)
+		err = opTerm.errIncompatibleType(childValue)
 	}
 	return
 }

operator-prod.go

@@ -14,8 +14,6 @@ import (
 func newMultiplyTerm(tk *Token) (inst *term) {
 	return &term{
 		tk: *tk,
-		// class:    classOperator,
-		// kind:     kindUnknown,
 		children: make([]*term, 0, 2),
 		position: posInfix,
 		priority: priProduct,
@@ -23,10 +21,10 @@ func newMultiplyTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalMultiply(ctx ExprContext, self *term) (v any, err error) {
+func evalMultiply(ctx ExprContext, prodTerm *term) (v any, err error) {
 	var leftValue, rightValue any
 
-	if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
+	if leftValue, rightValue, err = prodTerm.evalInfix(ctx); err != nil {
 		return
 	}
 
@@ -45,7 +43,7 @@ func evalMultiply(ctx ExprContext, self *term) (v any, err error) {
 			v = leftInt * rightInt
 		}
 	} else {
-		err = self.errIncompatibleTypes(leftValue, rightValue)
+		err = prodTerm.errIncompatibleTypes(leftValue, rightValue)
 	}
 	return
 }
@@ -55,8 +53,6 @@ func evalMultiply(ctx ExprContext, self *term) (v any, err error) {
 func newDivideTerm(tk *Token) (inst *term) {
 	return &term{
 		tk: *tk,
-		// class:    classOperator,
-		// kind:     kindUnknown,
 		children: make([]*term, 0, 2),
 		position: posInfix,
 		priority: priProduct,
@@ -64,10 +60,10 @@ func newDivideTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalDivide(ctx ExprContext, self *term) (v any, err error) {
+func evalDivide(ctx ExprContext, opTerm *term) (v any, err error) {
 	var leftValue, rightValue any
 
-	if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
+	if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
 		return
 	}
 
@@ -90,7 +86,7 @@ func evalDivide(ctx ExprContext, self *term) (v any, err error) {
 			}
 		}
 	} else {
-		err = self.errIncompatibleTypes(leftValue, rightValue)
+		err = opTerm.errIncompatibleTypes(leftValue, rightValue)
 	}
 	return
 }
@@ -107,10 +103,10 @@ func newDivideAsFloatTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalDivideAsFloat(ctx ExprContext, self *term) (v any, err error) {
+func evalDivideAsFloat(ctx ExprContext, floatDivTerm *term) (v any, err error) {
 	var leftValue, rightValue any
 
-	if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
+	if leftValue, rightValue, err = floatDivTerm.evalInfix(ctx); err != nil {
 		return
 	}
 
@@ -122,18 +118,16 @@ func evalDivideAsFloat(ctx ExprContext, self *term) (v any, err error) {
 			v = numAsFloat(leftValue) / d
 		}
 	} else {
-		err = self.errIncompatibleTypes(leftValue, rightValue)
+		err = floatDivTerm.errIncompatibleTypes(leftValue, rightValue)
 	}
 	return
 }
 
 //-------- reminder term
 
-func newReminderTerm(tk *Token) (inst *term) {
+func newRemainderTerm(tk *Token) (inst *term) {
 	return &term{
 		tk: *tk,
-		// class:    classOperator,
-		// kind:     kindUnknown,
 		children: make([]*term, 0, 2),
 		position: posInfix,
 		priority: priProduct,
@@ -141,10 +135,10 @@ func newReminderTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalReminder(ctx ExprContext, self *term) (v any, err error) {
+func evalReminder(ctx ExprContext, ramainderTerm *term) (v any, err error) {
 	var leftValue, rightValue any
 
-	if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
+	if leftValue, rightValue, err = ramainderTerm.evalInfix(ctx); err != nil {
 		return
 	}
 
@@ -157,7 +151,7 @@ func evalReminder(ctx ExprContext, self *term) (v any, err error) {
 			v = leftInt % rightInt
 		}
 	} else {
-		err = self.errIncompatibleTypes(leftValue, rightValue)
+		err = ramainderTerm.errIncompatibleTypes(leftValue, rightValue)
 	}
 	return
 }
@@ -167,5 +161,5 @@ func init() {
 	registerTermConstructor(SymStar, newMultiplyTerm)
 	registerTermConstructor(SymSlash, newDivideTerm)
 	registerTermConstructor(SymDotSlash, newDivideAsFloatTerm)
-	registerTermConstructor(SymPercent, newReminderTerm)
+	registerTermConstructor(SymPercent, newRemainderTerm)
 }

operator-range.go

@@ -34,25 +34,25 @@ func newRangeTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalRange(ctx ExprContext, self *term) (v any, err error) {
+func evalRange(ctx ExprContext, opTerm *term) (v any, err error) {
 	var leftValue, rightValue any
 
 	// if err = self.checkOperands(); err != nil {
 	// 	return
 	// }
-	if len(self.children) == 0 {
+	if len(opTerm.children) == 0 {
 		leftValue = int64(0)
 		rightValue = int64(-1)
-	} else if len(self.children) == 1 {
+	} else if len(opTerm.children) == 1 {
-		if leftValue, err = self.children[0].compute(ctx); err != nil {
+		if leftValue, err = opTerm.children[0].compute(ctx); err != nil {
 			return
 		}
 		rightValue = int64(ConstLastIndex)
-	} else if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
+	} else if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
 		return
 	}
 	if !(IsInteger(leftValue) && IsInteger(rightValue)) {
-		err = self.errIncompatibleTypes(leftValue, rightValue)
+		err = opTerm.errIncompatibleTypes(leftValue, rightValue)
 		return
 	}
 

operator-rel.go

@@ -45,10 +45,10 @@ func equals(a, b any, deepCmp deepFuncTemplate) (eq bool, err error) {
 	return
 }
 
-func evalEqual(ctx ExprContext, self *term) (v any, err error) {
+func evalEqual(ctx ExprContext, opTerm *term) (v any, err error) {
 	var leftValue, rightValue any
 
-	if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
+	if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
 		return
 	}
 
@@ -68,8 +68,8 @@ func newNotEqualTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalNotEqual(ctx ExprContext, self *term) (v any, err error) {
+func evalNotEqual(ctx ExprContext, opTerm *term) (v any, err error) {
-	if v, err = evalEqual(ctx, self); err == nil {
+	if v, err = evalEqual(ctx, opTerm); err == nil {
 		b, _ := ToBool(v)
 		v = !b
 	}
@@ -119,13 +119,13 @@ func lessThan(self *term, a, b any) (isLess bool, err error) {
 	return
 }
 
-func evalLess(ctx ExprContext, self *term) (v any, err error) {
+func evalLess(ctx ExprContext, opTerm *term) (v any, err error) {
 	var leftValue, rightValue any
 
-	if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
+	if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
 		return
 	}
-	v, err = lessThan(self, leftValue, rightValue)
+	v, err = lessThan(opTerm, leftValue, rightValue)
 	return
 }
 
@@ -154,14 +154,14 @@ func lessThanOrEqual(self *term, a, b any) (isLessEq bool, err error) {
 	return
 }
 
-func evalLessEqual(ctx ExprContext, self *term) (v any, err error) {
+func evalLessEqual(ctx ExprContext, opTerm *term) (v any, err error) {
 	var leftValue, rightValue any
 
-	if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
+	if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
 		return
 	}
 
-	v, err = lessThanOrEqual(self, leftValue, rightValue)
+	v, err = lessThanOrEqual(opTerm, leftValue, rightValue)
 
 	return
 }
@@ -178,14 +178,14 @@ func newGreaterTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalGreater(ctx ExprContext, self *term) (v any, err error) {
+func evalGreater(ctx ExprContext, opTerm *term) (v any, err error) {
 	var leftValue, rightValue any
 
-	if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
+	if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
 		return
 	}
 
-	v, err = lessThan(self, rightValue, leftValue)
+	v, err = lessThan(opTerm, rightValue, leftValue)
 	return
 }
 
@@ -201,14 +201,14 @@ func newGreaterEqualTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalGreaterEqual(ctx ExprContext, self *term) (v any, err error) {
+func evalGreaterEqual(ctx ExprContext, opTerm *term) (v any, err error) {
 	var leftValue, rightValue any
 
-	if leftValue, rightValue, err = self.evalInfix(ctx); err != nil {
+	if leftValue, rightValue, err = opTerm.evalInfix(ctx); err != nil {
 		return
 	}
 
-	v, err = lessThanOrEqual(self, rightValue, leftValue)
+	v, err = lessThanOrEqual(opTerm, rightValue, leftValue)
 	return
 }
 

operator-selector.go

@@ -39,19 +39,19 @@ func trySelectorCase(ctx ExprContext, exprValue, caseSel any, caseIndex int) (ma
 	return
 }
 
-func evalSelector(ctx ExprContext, self *term) (v any, err error) {
+func evalSelector(ctx ExprContext, opTerm *term) (v any, err error) {
 	var exprValue any
 	var match bool
 
-	if err = self.checkOperands(); err != nil {
+	if err = opTerm.checkOperands(); err != nil {
 		return
 	}
-	exprTerm := self.children[0]
+	exprTerm := opTerm.children[0]
 	if exprValue, err = exprTerm.compute(ctx); err != nil {
 		return
 	}
 
-	caseListTerm := self.children[1]
+	caseListTerm := opTerm.children[1]
 	caseList, _ := caseListTerm.value().([]*term)
 	for i, caseTerm := range caseList {
 		caseSel := caseTerm.value()

operator-sign.go

@@ -28,29 +28,29 @@ func newMinusSignTerm(tk *Token) (inst *term) {
 	}
 }
 
-func evalSign(ctx ExprContext, self *term) (v any, err error) {
+func evalSign(ctx ExprContext, opTerm *term) (v any, err error) {
 	var rightValue any
 
-	if rightValue, err = self.evalPrefix(ctx); err != nil {
+	if rightValue, err = opTerm.evalPrefix(ctx); err != nil {
 		return
 	}
 
 	if IsFloat(rightValue) {
-		if self.tk.Sym == SymChangeSign {
+		if opTerm.tk.Sym == SymChangeSign {
 			f, _ := rightValue.(float64)
 			v = -f
 		} else {
 			v = rightValue
 		}
 	} else if IsInteger(rightValue) {
-		if self.tk.Sym == SymChangeSign {
+		if opTerm.tk.Sym == SymChangeSign {
 			i, _ := rightValue.(int64)
 			v = -i
 		} else {
 			v = rightValue
 		}
 	} else {
-		err = self.errIncompatibleType(rightValue)
+		err = opTerm.errIncompatibleType(rightValue)
 	}
 	return
 }