luaforwindows/files/lua/debug_ext.lua

84 lines
2.2 KiB
Lua

--- Additions to the debug module
module ("debug", package.seeall)
require "debug_init"
require "io_ext"
require "string_ext"
--- To activate debugging set _DEBUG either to any true value
-- (equivalent to {level = 1}), or as documented below.
-- @class table
-- @name _DEBUG
-- @field level debugging level
-- @field call do call trace debugging
-- @field std do standard library debugging (run examples & test code)
--- Print a debugging message
-- @param n debugging level, defaults to 1
-- @param ... objects to print (as for print)
function say (n, ...)
local level = 1
local arg = {n, ...}
if type (arg[1]) == "number" then
level = arg[1]
table.remove (arg, 1)
end
if _DEBUG and
((type (_DEBUG) == "table" and type (_DEBUG.level) == "number" and
_DEBUG.level >= level)
or level <= 1) then
io.writeline (io.stderr, table.concat (list.map (tostring, arg), "\t"))
end
end
---
-- debug.say is also available as the global function <code>debug</code>
-- @class function
-- @name debug
-- @see say
getmetatable (_M).__call =
function (self, ...)
say (...)
end
--- Trace function calls
-- Use as debug.sethook (trace, "cr"), which is done automatically
-- when _DEBUG.call is set.
-- Based on test/trace-calls.lua from the Lua distribution.
-- @class function
-- @name trace
-- @param event event causing the call
local level = 0
function trace (event)
local t = getinfo (3)
local s = " >>> " .. string.rep (" ", level)
if t ~= nil and t.currentline >= 0 then
s = s .. t.short_src .. ":" .. t.currentline .. " "
end
t = getinfo (2)
if event == "call" then
level = level + 1
else
level = math.max (level - 1, 0)
end
if t.what == "main" then
if event == "call" then
s = s .. "begin " .. t.short_src
else
s = s .. "end " .. t.short_src
end
elseif t.what == "Lua" then
s = s .. event .. " " .. (t.name or "(Lua)") .. " <" ..
t.linedefined .. ":" .. t.short_src .. ">"
else
s = s .. event .. " " .. (t.name or "(C)") .. " [" .. t.what .. "]"
end
io.writeline (io.stderr, s)
end
-- Set hooks according to _DEBUG
if type (_DEBUG) == "table" and _DEBUG.call then
sethook (trace, "cr")
end