server/scripts/dumptable.lua

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-- Return indentation string for passed level
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local function tabs(i)
    return string.rep(".",i).." "   -- Dots followed by a space
end

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-- Return string representation of parameter's value & type
-----------------------------------------------------------
local function toStrType(t)
    local function fttu2hex(t) -- Grab hex value from tostring() output
        local str = tostring(t);
        if str == nil then
            return "tostring() failure! \n"
        else
            local str2 = string.match(str,"[ :][ (](%x+)")
            if str2 == nil then
                return "string.match() failure: "..str.."\n"
            else
                return "0x"..str2
            end
        end
    end
    -- Stringify a value of a given type using a table of functions keyed
    -- by the name of the type (Lua's version of C's switch() statement).
    local stringify = {
        -- Keys are all possible strings that type() may return,
        -- per http://www.lua.org/manual/5.1/manual.html#pdf-type.
        ["nil"]			= function(v) return "nil (nil)"			    end,
        ["string"]		= function(v) return '"'..v..'" (string)'	    end,
        ["number"]		= function(v) return v.." (number)"			    end,
        ["boolean"]		= function(v) return tostring(v).." (boolean)"  end,
        ["function"]	= function(v) return fttu2hex(v).." (function)" end,
        ["table"]		= function(v) return fttu2hex(v).." (table)"	end,
        ["thread"]		= function(v) return fttu2hex(v).." (thread)"	end,
        ["userdata"]	= function(v) return fttu2hex(v).." (userdata)" end
    }
    return stringify[type(t)](t)
end

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-- Count elements in the passed table
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local function lenTable(t)		-- What Lua builtin does this simple thing?
    local n=0                   -- '#' doesn't work with mixed key types
    if ("table" == type(t)) then
        for key in pairs(t) do  -- Just count 'em
            n = n + 1
        end
        return n
    else
        return nil
    end
end

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-- Pretty-print the passed table
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local function do_dumptable(t, indent, seen)
    -- "seen" is an initially empty table used to track all tables
    -- that have been dumped so far.  No table is dumped twice.
    -- This also keeps the code from following self-referential loops,
    -- the need for which was found when first dumping "_G".
    if ("table" == type(t)) then	-- Dump passed table
        seen[t] = 1
        if (indent == 0) then
            print ("The passed table has "..lenTable(t).." entries:")
            indent = 1
        end
        for f,v in pairsByKeys(t) do
            if ("table" == type(v)) and (seen[v] == nil) then    -- Recurse
                print( tabs(indent)..toStrType(f).." has "..lenTable(v).." entries: {")
                do_dumptable(v, indent+1, seen)
                print( tabs(indent).."}" )
            else
                print( tabs(indent)..toStrType(f).." = "..toStrType(v))
            end
        end
    else
        print (tabs(indent).."Not a table!")
    end
end

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-- Wrapper to handle persistence
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function dumptable(t)   -- Only global declaration in the package
    -- This wrapper exists only to set the environment for the first run:
    -- The second param is the indentation level.
    -- The third param is the list of tables dumped during this call.
    -- Getting this list allocated and freed was a pain, and this
    -- wrapper was the best solution I came up with...
    return do_dumptable(t, 0, {})
end