Merge pull request #2106 from xushiwei/q

pseudo: parseNames
goplus · Feb 15, 2025 · 5fd7c0b · 5fd7c0b
2 parents 8a109dd + 1016ce2
commit 5fd7c0b
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Showing 3 changed files with 39 additions and 33 deletions.
diff --git a/demo/gop-parser/pseudo/ast.gop b/demo/gop-parser/pseudo/ast.gop
@@ -51,9 +51,9 @@ type OutputStmt struct {
 
 // InputStmt - 输入语句
 //
-// INPUT {变量名}
+// INPUT {变量名1}, {变量名2}...
 type InputStmt struct {
-	Name string
+	Names []string
 }
 
 // IfStmt - 条件语句
@@ -79,7 +79,7 @@ type WhileStmt struct {
 	Body []Stmt
 }
 
-// UntilStmt - Unti循环语句
+// UntilStmt - Until循环语句
 //
 // REPEAT
 //	 {语句块}

diff --git a/demo/gop-parser/pseudo/parser.gop b/demo/gop-parser/pseudo/parser.gop
@@ -66,6 +66,28 @@ func parseType(s *scanner.Scanner) Type {
 	return &Ident{Name: name}
 }
 
+// {变量名1}, {变量名2}...
+func parseNames(s *scanner.Scanner) (names []string, tok token.Token) {
+	for {
+		_, name := expect(s, token.IDENT) // {名称}
+		names = append(names, name)
+		_, tok, _ = s.scan()
+		if tok == token.COMMA { // ,
+			continue
+		}
+		return
+	}
+}
+
+// {常量名} <- {表达式}
+func parseNameAndValue(rest string) (string, ast.Expr) {
+	s := scanner.new(rest, nil, 0)
+	_, name := expect(s, token.IDENT) // {名称}
+	pos, _ := expect(s, token.ARROW)  // <-
+	value := parseExpr(rest[pos+1:])  // {表达式}
+	return name, value
+}
+
 // Expr - 表达式
 func parseExpr(expr string) ast.Expr {
 	e, err := parser.parseExpr(expr)
@@ -80,31 +102,14 @@ func parseExpr(expr string) ast.Expr {
 // DECLARE {变量名1}, {变量名2}... : {类型}
 func parseVarStmt(rest string, lines []string) (Stmt, []string) {
 	s := scanner.new(rest, nil, 0)
-	var names []string
-	for {
-		_, name := expect(s, token.IDENT) // {名称}
-		names = append(names, name)
-		_, tok, _ := s.scan()
-		if tok == token.COMMA { // ,
-			continue
-		} else if tok == token.COLON { // :
-			break
-		} else {
-			panic("DECLARE: expect , or :")
-		}
+	names, tok := parseNames(s) // {变量名1}, {变量名2}...
+	if tok != token.COLON {     // :
+		panic("DECLARE: expect , or :")
 	}
 	typ := parseType(s) // {类型}
 	return &VarStmt{Names: names, Type: typ}, lines[1:]
 }
 
-func parseNameAndValue(rest string) (string, ast.Expr) {
-	s := scanner.new(rest, nil, 0)
-	_, name := expect(s, token.IDENT) // {名称}
-	pos, _ := expect(s, token.ARROW)  // <-
-	value := parseExpr(rest[pos+1:])  // {表达式}
-	return name, value
-}
-
 // ConstStmt - 常量声明语句
 //
 // CONSTANT {常量名} <- {表达式}
@@ -131,11 +136,11 @@ func parseOutputStmt(rest string, lines []string) (Stmt, []string) {
 
 // InputStmt - 输入语句
 //
-// INPUT {变量名}
+// INPUT {变量名1}, {变量名2}...
 func parseInputStmt(rest string, lines []string) (Stmt, []string) {
 	s := scanner.new(rest, nil, 0)
-	_, name := expect(s, token.IDENT) // {变量名}
-	return &InputStmt{Name: name}, lines[1:]
+	names, _ := parseNames(s)
+	return &InputStmt{Names: names}, lines[1:]
 }
 
 // IfStmt - If 语句

diff --git a/demo/gop-parser/pseudo/state.gox b/demo/gop-parser/pseudo/state.gox
@@ -80,14 +80,15 @@ func execOutputStmt(stmt *OutputStmt) {
 }
 
 func execInputStmt(stmt *InputStmt) {
-	name := stmt.Name
-	oldv, ok := vars[name]
-	if !ok {
-		panic("undefined variable `${name}`")
+	for name <- stmt.Names {
+		oldv, ok := vars[name]
+		if !ok {
+			panic("undefined variable `${name}`")
+		}
+		v := reflect.new(reflect.typeOf(oldv))
+		fmt.scanln(v.Interface())!
+		vars[name] = v.elem.Interface()
 	}
-	v := reflect.new(reflect.typeOf(oldv))
-	fmt.scanln(v.Interface())!
-	vars[name] = v.elem.Interface()
 }
 
 func execIfStmt(stmt *IfStmt) {