Strict types

tool/rawstr4c/lib/Parser.rakumod

@@ -13,10 +13,10 @@
 unit module Parser;
 
 #| 不能用 Bool，只能用 Boolean
-my enum ConfigItem's-ValueType <String Mode Boolean>;
+my enum ConfigItem's-ValueType < RS4C-Nil RS4C-String RS4C-Mode RS4C-Bool>;
 
 #| 配置项的值
-my class ConfigItem's-Value {
+class ConfigItem's-Value {
   has ConfigItem's-ValueType $.type;
   has Str                    $.raw-value;
   has Any                    $.parsed-value;
@@ -28,17 +28,24 @@ my class ConfigItem's-Value {
     given $raw-text {
       when /^ ':' (.+) $/ {
         # 模式值 :mode
-        $type = Mode;
+        $type = RS4C-Mode;
         $parsed = ~$0;
       }
       when /^ ('true'|'false'|'yes'|'no') $/ {
         # 特殊字面量 - true/false/yes/no 都是 literal
-        $type = Boolean;
+        $type = RS4C-Bool;
         $parsed = ~$0 ~~ /^('true'|'yes')$/ ?? True !! False;
       }
+      # 明确区分空字符串和无值情况
+      # 这种情况不可能是用户写的(并没有nil这个字面量)，只由内部实现时刻意传 Nil 出现
+      when Nil {
+        $type = RS4C-Nil;
+        $parsed = Nil;
+      }
+      # 输入为空时被当做是字符串类型
       default {
         # 普通字符串
-        $type = String;
+        $type = RS4C-String;
         $parsed = $raw-text;
       }
     }
@@ -46,30 +53,41 @@ my class ConfigItem's-Value {
     self.bless(:$type, :raw-value($raw-text), :parsed-value($parsed));
   }
 
-  method as-string() {
-    return $.parsed-value.Str;
-  }
-
-  method as-bool() {
+  # 获得适合调用者接受的值
+  method value() {
     given $.type {
-      when Boolean { return $.parsed-value; }
-      when String  {
-        # 尝试将字符串解析为布尔值
-        return $.parsed-value ~~ /^('true'|'yes')$/;
-      }
-      default { return False; }
+      when RS4C-Nil | RS4C-String | RS4C-Bool | RS4C-Mode  { return $.parsed-value; }
+      default { die "Unknown config value type: {$.type}"; }
     }
   }
 
-  # 获取模式值（去掉冒号前缀）
-  method as-mode() {
-    return $.type == Mode ?? $.parsed-value !! $.raw-value;
+  # 这些函数防止开发者写错类型
+  method nil-value() {
+    return self.value if $.type == RS4C-Nil;
+    die "The config value type is not RS4C-Nil, but: {$.type}";
   }
 
+  method string-value() {
+    return self.value if $.type == RS4C-String;
+    die "The config value type is not RS4C-String, but: {$.type}";
+  }
+
+  method bool-value() {
+    return self.value if $.type == RS4C-Bool;
+    die "The config value type is not RS4C-Bool, but: {$.type}";
+  }
+
+  method mode-value() {
+    return self.value if $.type == RS4C-Mode;
+    die "The config value type is not RS4C-Mode, but: {$.type}";
+  }
+
+
   # 类型检查方法
-  method is-mode() { return $.type == Mode; }
-  method is-bool() { return $.type == Boolean; }
-  method is-string() { return $.type == String; }
+  method is-nil()  { return $.type == RS4C-Nil; }
+  method is-mode() { return $.type == RS4C-Mode; }
+  method is-bool() { return $.type == RS4C-Bool; }
+  method is-string() { return $.type == RS4C-String; }
 }
 
 
@@ -85,8 +103,8 @@ my class ConfigBlock {
     %!items{$k} = ConfigItem's-Value.new($raw-value);
   }
 
-  method get($k, $default = Nil) {
-    return %!items{$k} // ($default ?? ConfigItem's-Value.new($default) !! ConfigItem's-Value.new(''));
+  method get($k) {
+    return %!items{$k};
   }
 
   method exist($k) {
@@ -102,7 +120,7 @@ my class ConfigBlock {
 
 
 #| 表示一个 section
-my class Section {
+class Section {
 
   has Str         $.title;
   has Int         $.level;