hash.c: implement typical part of merge in C.

mrbgems/mruby-hash-ext/mrblib/hash.rb

@@ -83,6 +83,7 @@ class Hash
 
   def merge!(*others, &block)
     i = 0; len=others.size
+    return self.__merge(*others) unless block
     while i<len
       other = others[i]
       i += 1

mrblib/hash.rb

@@ -161,17 +161,14 @@ class Hash
   def merge(*others, &block)
     i=0; len=others.size
     h = self.dup
+    return h.__merge(*others) unless block
     while i<len
       other = others[i]
       i += 1
       raise TypeError, "Hash required (#{other.class} given)" unless Hash === other
-      if block
-        other.each_key{|k|
-          h[k] = (self.has_key?(k))? block.call(k, self[k], other[k]): other[k]
-        }
-      else
-        other.each_key{|k| h[k] = other[k]}
-      end
+      other.each_key{|k|
+        h[k] = (self.has_key?(k))? block.call(k, self[k], other[k]): other[k]
+      }
     end
     h
   end

src/hash.c

@@ -1746,6 +1746,19 @@ mrb_hash_merge(mrb_state *mrb, mrb_value hash1, mrb_value hash2)
   });
 }
 
+static mrb_value
+mrb_hash_merge_m(mrb_state *mrb, mrb_value hash)
+{
+  mrb_int argc;
+  mrb_value *argv;
+
+  mrb_get_args(mrb, "*", &argv, &argc);
+  while (argc--) {
+    mrb_hash_merge(mrb, hash, *argv++);
+  }
+  return hash;
+}
+
 /*
  *  call-seq:
  *    hsh.rehash -> hsh
@@ -1806,4 +1819,5 @@ mrb_init_hash(mrb_state *mrb)
   mrb_define_method(mrb, h, "value?",          mrb_hash_has_value,   MRB_ARGS_REQ(1)); /* 15.2.13.4.27 */
   mrb_define_method(mrb, h, "values",          mrb_hash_values,      MRB_ARGS_NONE()); /* 15.2.13.4.28 */
   mrb_define_method(mrb, h, "rehash",          mrb_hash_rehash,      MRB_ARGS_NONE());
+  mrb_define_method(mrb, h, "__merge",         mrb_hash_merge_m,     MRB_ARGS_REQ(1));
 }