lua: move non-core code out of vis.lua

The following structure is adapted:

 * visrc.lua entry point for all Lua code

 * vis.lua only implements the Lua part of the core API

 * vis-std.lua registers standard event handlers (e.g. syntax highlighting,
   statusbar handling, theme changes etc). It is sourced from vis.lua.

 * plugins/* non essential editor functionality, needs to be explicitly
   enabled by loading it from visrc.lua

1 files changed, 34 insertions, 0 deletions

diff --git a/lua/plugins/textobject-lexer.lua b/lua/plugins/textobject-lexer.lua
new file mode 100644
index 0000000..a995083
--- /dev/null
+++ b/lua/plugins/textobject-lexer.lua
@@ -0,0 +1,34 @@
+-- text object matching a lexer token
+
+local MAX_CONTEXT = 32768
+
+vis:textobject_new("ii", function(win, pos)
+
+	if win.syntax == nil or not vis.lexers then
+		return pos, pos
+	end
+
+	local before, after = pos - MAX_CONTEXT, pos + MAX_CONTEXT
+	if before < 0 then
+		before = 0
+	end
+	-- TODO make sure we start at a line boundary?
+
+	local lexer = vis.lexers.load(win.syntax)
+	local data = win.file:content(before, after - before)
+	local tokens = lexer:lex(data)
+	local cur = before
+	-- print(before..", "..pos..", ".. after)
+
+	for i = 1, #tokens, 2 do
+		local name = tokens[i]
+		local token_next = before + tokens[i+1] - 1
+		-- print(name..": ["..cur..", "..token_next.."] pos: "..pos)
+		if cur <= pos and pos < token_next then
+			return cur, token_next
+		end
+		cur = token_next
+	end
+
+	return pos, pos
+end)