Add missing ctl::string append method

Author: jart

ctl/string.cc

@@ -383,4 +383,10 @@ string::erase(const size_t pos, size_t count) noexcept
     return *this;
 }
 
+void
+string::append(const ctl::string_view& s, size_t pos, size_t count) noexcept
+{
+    append(s.substr(pos, count));
+}
+
 } // namespace ctl

ctl/string.h

@@ -125,6 +125,7 @@ class string
     void append(char, size_t) noexcept;
     void append(unsigned long) noexcept;
     void append(const void*, size_t) noexcept;
+    void append(const ctl::string_view&, size_t, size_t = npos) noexcept;
     string& insert(size_t, ctl::string_view) noexcept;
     string& erase(size_t = 0, size_t = npos) noexcept;
     string substr(size_t = 0, size_t = npos) const noexcept;
@@ -302,7 +303,7 @@ class string
         append(ch);
     }
 
-    void append(const ctl::string_view s) noexcept
+    void append(const ctl::string_view& s) noexcept
     {
         append(s.p, s.n);
     }

test/ctl/string_test.cc

@@ -404,5 +404,13 @@ main()
         }
     }
 
+    {
+        String s = "love";
+        String b;
+        b.append(s, 1, 2);
+        if (b != "ov")
+            return 107;
+    }
+
     CheckForMemoryLeaks();
 }