基础版词法分析

lexical.go

@@ -8,6 +8,7 @@
 package filter
 
 import (
+	"encoding/json"
 	"fmt"
 
 	"github.com/pkg/errors"
@@ -18,13 +19,37 @@ import (
 // Author : go_developer@163.com<白茶清欢>
 //
 // Date : 18:11 2022/7/4
-func parseLexical(jsonData string) ([]*lexicalNode, error) {
+func parseLexical(jsonData string) ([]lexicalNode, error) {
 	if len(jsonData) < 2 {
 		return nil, errors.New("input data is not json")
 	}
+	lexicalList := make([]lexicalNode, 0)
+	tmpStr := ""
 	for _, itemChar := range jsonData {
-		fmt.Println("============ : ", string(itemChar))
+		currentChar := string(itemChar)
+		preChar := "-1"
+		if len(lexicalList) > 0 {
+			preChar = lexicalList[len(lexicalList)-1].Val
+		}
+		if inputCharIsToken(currentChar, preChar) {
+			// 是关键词
+			if len(tmpStr) > 0 {
+				lexicalList = append(lexicalList, lexicalNode{
+					Val:     tmpStr,
+					IsToken: false,
+				})
+			}
+			lexicalList = append(lexicalList, lexicalNode{
+				Val:     currentChar,
+				IsToken: true,
+			})
+		} else {
+			// 不是关键词, 继续向后走
+			tmpStr = tmpStr + currentChar
+		}
 	}
+	byteData, _ := json.Marshal(lexicalList)
+	fmt.Println("============ : ", string(byteData))
 	return nil, nil
 }
 
@@ -33,13 +58,17 @@ func parseLexical(jsonData string) ([]*lexicalNode, error) {
 // Author : go_developer@163.com<白茶清欢>
 //
 // Date : 18:15 2022/7/4
-func inputCharIsToken(inputChar string) bool {
+func inputCharIsToken(inputChar string, preChar string) bool {
+	if preChar == escapeCharacterToken {
+		// 前一个是转义符, 当前不是关键字
+		return false
+	}
 	tokenCharList := []string{
 		listLeftToken,
 		listRightToken,
 		objectLeftToken,
 		objectRightToken,
-		keyRightToken,
+		keyLeftRightToken,
 		kvPairSplitToken,
 		escapeCharacterToken,
 	}

token.go

@@ -17,12 +17,9 @@ const (
 	// 对象结束
 	objectRightToken = "}"
 	// key 值的起始
-	keyLeftToken = "\""
-	// key 值的结束
-	keyRightToken = "\""
+	keyLeftRightToken = "\""
 	// kvPairSplit kv 的分隔符
 	kvPairSplitToken = ":"
 	// 转义符
 	escapeCharacterToken = "\\"
 )
-