fix: nil because i'm new on lua

README.md

@@ -54,11 +54,6 @@ local ts = require('tsql')
 ts.t(ts.buf_match.any(), ts.ts_query.from_scm("string"), ts.sink_by.print()):do_nvim()
 ```
 
-Here's the same thing in a one-liner
-```lua
-:lua local ts = require('tsql'); ts.t(ts.buf_match.any(), ts.ts_query.from_scm("string"), ts.sink_by.print()):do_nvim()
-```
-
 ## Installation
 
 Use your favorite package manager to install the plugin. For example, with [vim-plug](https://github.com/junegunn/vim-plug):

lua/tsql.lua

@@ -17,38 +17,37 @@ M.sink_by = {}
 ---@alias Format fun(nodes: QNode[]): string
 M.format = {}
 
-M.format.default = M.format.display
 
 ---@class Sink
 ---@field sink fun(self, nodes: QNode[])
 M.Sink = {}
 M.Sink.__index = M.Sink
 
----@return Sink
+---@type Ctor<fun(nodes: QNode[]), Sink>
----@param func fun(self, nodes:QNode[])
 function M.sink_by.pure_fn(func)
-    return setmetatable({
+    local self = setmetatable({
-        sink = func
+        sink = function(_, nodes)
+            return func(nodes)
+        end
     }, M.Sink)
+    self.__index = M.Sink
+    return self
 end
 
 ---@return Sink
 function M.sink_by.highlight()
-    return setmetatable({
+    return M.sink_by.pure_fn(function(nodes)
-        ---@type fun(nodes: QNode[])
+        for _, node in ipairs(nodes) do
-        sink = function(nodes)
+            vim.highlight.range(
-            for _, node in ipairs(nodes) do
+                node.buf.bufnr,
-                vim.highlight.range(
+                M.config.nvim_ns,
-                    node.buf.bufnr,
+                M.config.nvim_hl_group,
-                    M.config.nvim_ns,
+                { node.start.row_0, node.start.col_0 },
-                    M.config.nvim_hl_group,
+                { node.end_ex_col.row_0, node.end_ex_col.col_0 },
-                    { node.start.row_0, node.start.col_0 },
+                {}
-                    { node.end_ex_col.row_0, node.end_ex_col.col_0 },
+            )
-                    {}
-                )
-            end
         end
-    }, M.Sink)
+    end)
 end
 
 ---@type Format
@@ -67,8 +66,14 @@ end
 function M.format.display(nodes)
     local texts = {}
     for _, node in ipairs(nodes) do
-        local text = vim.api.nvim_buf_get_text(node.buf.bufnr, node.start.row_0, node.start.col_0, node.end_ex_col.row_0,
+        local text = vim.api.nvim_buf_get_text(
-            node.end_ex_col.col_0)
+            node.buf.bufnr,
+            node.start.row_0,
+            node.start.col_0,
+            node.end_ex_col.row_0,
+            node.end_ex_col.col_0,
+            {}
+        )
         table.insert(texts, table.concat(text, '\n'))
     end
     return table.concat(texts, '\n\n')
@@ -83,6 +88,7 @@ function M.format.dump(nodes)
 end
 
 M.format.debug = M.format.dump
+M.format.default = M.format.display
 
 ---@param format Format | nil
 ---@return Sink
@@ -214,6 +220,7 @@ end
 function M.Store:new()
     local o = { highlighting = {} }
     setmetatable(o, self)
+    self.__index = self
     return o
 end
 
@@ -233,6 +240,7 @@ function M.setup(config)
     end, { nargs = "?", desc = "tsql DSL invocation" })
 
     M.store = M.Store:new()
+    print("tsql v0.0.1")
 end
 
 return M

lua/tsql/buf_select.lua

@@ -15,6 +15,7 @@ local M = {}
 ---from `vim.treesitter.get_parser(bufnr: number):lang() -> string [may fail]`
 ---@field is_loaded boolean whether it is loaded
 M.QBuf = {}
+M.QBuf.__index = M.QBuf
 
 ---@return string language
 ---NOTE: may fail with string
@@ -52,7 +53,7 @@ function M.QBuf:new(bufnr, path, filetype, lang, is_loaded)
         is_loaded = is_loaded
     }
     setmetatable(qbuf, self)
-    self.__index = self
+    qbuf.__index = self
     return qbuf
 end
 
@@ -86,6 +87,7 @@ end
 ---NOTE: assigns `match_fn` private field
 function M.BufMatch.new(match_fn)
     local self = setmetatable({}, M.BufMatch)
+    self.__index = M.BufMatch
     self.match_fn = match_fn
     return self
 end

lua/tsql/category.lua

@@ -0,0 +1,10 @@
+-- Interface-only file for type-hints
+--
+
+---@generic T
+---@generic R
+---
+---@alias Ctor<T, R> fun(arg: T): R
+---A good practice is to only has a single argument per ctor/class method.
+---If you need multiple arguments, having explicit names is much better than
+---positional args, unless you want currying.

repl.md

@@ -0,0 +1,13 @@
+# Simple location for me to use as a neovim repl
+
+```lua
+:lua local ts = require('tsql'); ts.t(ts.buf_match.any(), ts.ts_query.from_scm("string"), ts.sink_by.print()):do_nvim();
+
+:lua local ts = require('tsql'); local tsql = ts.t(ts.buf_match.any(), ts.ts_query.from_scm("string"), ts.sink_by.print()); print(vim.inspect(tsql.buf_match));
+
+-- print found bufs
+:lua local t = require('tsql'); print(vim.inspect(t.nvim_get_qbufs()))
+
+-- check that buf filter works
+:lua local t = require('tsql'); print(vim.inspect(t.buf_match.any():filter_on(t.nvim_get_qbufs())))
+```