build: add the basic type declaration (#30)

src/parser/flinksql.ts

@@ -9,7 +9,7 @@ export default class FlinkSQL extends BasicParser {
         const lexer = <unknown> new FlinkSqlLexer(chars) as Lexer;
         return lexer;
     }
-    public createParserFromLexer(lexer: Lexer) {
+    public createParserFromLexer(lexer: Lexer): any {
         const tokenStream = new CommonTokenStream(lexer);
         return new FlinkSqlParser(tokenStream);
     }

src/parser/generic.ts

@@ -9,7 +9,7 @@ export default class GenericSQL extends BasicParser {
         const lexer = <unknown> new SqlLexer(chars) as Lexer;
         return lexer;
     }
-    public createParserFromLexer(lexer: Lexer) {
+    public createParserFromLexer(lexer: Lexer): any {
         const tokenStream = new CommonTokenStream(lexer);
         return new SqlParser(tokenStream);
     }

src/parser/hive.ts

@@ -9,7 +9,7 @@ export default class HiveSQL extends BasicParser {
         const lexer = <unknown> new HiveSqlLexer(chars) as Lexer;
         return lexer;
     }
-    public createParserFromLexer(lexer: Lexer) {
+    public createParserFromLexer(lexer: Lexer): any {
         const tokenStream = new CommonTokenStream(lexer);
         return new HiveSql(tokenStream);
     }

src/parser/plsql.ts

@@ -10,7 +10,7 @@ export default class PLSQLParser extends BasicParser {
         const lexer = <unknown> new PlSqlLexer(chars) as Lexer;
         return lexer;
     }
-    public createParserFromLexer(lexer: Lexer) {
+    public createParserFromLexer(lexer: Lexer): any {
         const tokenStream = new CommonTokenStream(lexer);
         return new PlSqlParser(tokenStream);
     }

src/parser/spark.ts

@@ -9,7 +9,7 @@ export default class SparkSQL extends BasicParser {
         const lexer = <unknown> new SparkSqlLexer(chars) as Lexer;
         return lexer;
     }
-    public createParserFromLexer(lexer: Lexer) {
+    public createParserFromLexer(lexer: Lexer): any {
         const tokenStream = new CommonTokenStream(lexer);
         return new SparkSqlParser(tokenStream);
     }