local print = print
local debug = debug
local string = string
local io = io
local type = type
local pairs = pairs

module "dt"

function bt()
    local dinfo = debug.getinfo(2)
    local func_line = dinfo.linedefined
    local filename = dinfo.short_src
    local func_name = dinfo.name or"main"
    print ("func_line:", func_line, filename, func_name)

    local a =1
    local var_tb ={}
    while true
    do
        local name, value = debug.getlocal(2, a)
        if not name then break end

        var_tb[name]= value
        print(string.format("%s=", name), value)
        a = a +1
    end

    while true
    do
        io.write(string.format(">>"))
        local cmd = io.read()
        if cmd =="c"or cmd =="n"or cmd =="go"or cmd =="g"
        then
            break
        end

        local b = string.find(cmd," ")
        if b ==nil
        then
            print ("usage p + var")
        else
            local sub_cmd = string.sub(cmd,1, b-1)
            if sub_cmd =="p"or sub_cmd =="print"
                or sub_cmd =="dump"or sub_cmd =="d"
            then
                local sub_var = string.sub(cmd, b +1)
                local value = var_tb[sub_var]
                print(string.format("%s=", sub_var), value)

                if type(value)=="table"
                then
                    for k, v in pairs(value)
                    do
                        print("", k , v)
                    end
                end
            else
                print ("usage p + var", sub_cmd)
            end
        end
    end
end

--[[ 示例

require "dt"
dt.bt()

--]]