IncrementalInserter: add insert_capture method bound to ^B<num>

src/main.cc

@@ -284,6 +284,12 @@ void do_insert(Window& window, IncrementalInserter::Mode mode)
         case 27:
             return;
 
+        case 2:
+            c = getch();
+            if (c >= '0' and c <= '9')
+                inserter.insert_capture(c - '0');
+            break;
+
         case 4:
             inserter.move_cursor({0, -1});
             break;

src/window.cc

@@ -410,7 +410,7 @@ IncrementalInserter::IncrementalInserter(Window& window, Mode mode)
             ++pos;
             break;
         }
-        sel = Selection(pos, pos);
+        sel = Selection(pos, pos, sel.captures());
     }
 }
 
@@ -428,6 +428,13 @@ void IncrementalInserter::insert(const Window::String& string)
     m_window.insert_noundo(string);
 }
 
+void IncrementalInserter::insert_capture(size_t index)
+{
+    for (auto& sel : m_window.m_selections)
+        m_window.m_buffer.insert(sel.begin(), sel.capture(index));
+    m_window.scroll_to_keep_cursor_visible_ifn();
+}
+
 void IncrementalInserter::erase()
 {
     move_cursor(DisplayCoord(0, -1));

src/window.hh

@@ -142,6 +142,7 @@ public:
     ~IncrementalInserter();
 
     void insert(const Window::String& string);
+    void insert_capture(size_t index);
     void erase();
     void move_cursor(const DisplayCoord& offset);