Add exprmark.

1 files changed, 25 insertions, 4 deletions

diff --git a/plugin/mark.lua b/plugin/mark.lua
index dd3baa6..ccc6374 100644
--- a/plugin/mark.lua
+++ b/plugin/mark.lua
@@ -25,11 +25,10 @@ function middle_mark.set(self)
   api.nvim_command('norm z.')
 end
 
--- The top mark is the first line on the window. Right now scrolloff is ignored,
--- but maybe it shouldn't be.
+-- The top mark is the first line on the window. This does respect scrolloff.
 local top_mark = {}
 function top_mark.get(self)
-  return vim.api.nvim_call_function('line', {'w0'})
+  return vim.api.nvim_call_function('line', {'w0'}) + vim.o.scrolloff
 end
 -- Setting the top mark move the current line to the top. Principally this is
 -- the same mas z<cr>
@@ -41,14 +40,36 @@ end
 -- this is the same as z-
 local bottom_mark = {}
 function bottom_mark.get(self)
-  return vim.api.nvim_call_function('line', {'w$'})
+  return vim.api.nvim_call_function('line', {'w$'}) - vim.o.scrolloff
 end
 -- Setting the bottom mark doesn't do anything.
 function bottom_mark.set(self)
   api.nvim_command('norm z-')
 end
 
+-- Mark that's like the expression register, but for a mark.
+local expr_mark = {}
+function expr_mark.get(self)
+  local mode = vim.api.nvim_call_function('mode', {})
+
+  if mode == "c" then
+    -- Avoid recurring asking for a value while in command mode.
+    return nil
+  end
+
+  local expr = vim.api.nvim_call_function('input', {'='})
+  if expr ~= "" then
+    return vim.api.nvim_eval(expr)
+  end
+
+  return nil
+end
+
+-- Setting the expr_mark does'nt do anything
+function expr_mark.set(self) end
+
 -- Register all the marks with their respective characters.
 usermark.register_handler('-', middle_mark)
 usermark.register_handler('+', top_mark)
 usermark.register_handler('_', bottom_mark)
+usermark.register_handler('=', expr_mark)