Re: [ANN] vstruct - 1.0 beta 2

[Ben Kelly <ranavin@...>]

Christof Schardt wrote:
> In read.lua:
>    u = u * 2^8 + s:sub(i,i):byte()
> could be changed to
>    u = u * 2^8 + s:byte(i)

Good catch! I keep forgetting you can do that with byte().

> BTW: "2^8", will this this optimized by the interpreter, or
> should you rather write 256?

It'll be optimized. You can verify this with luac, a practice I highly
encourage:

$ echo 'return 2^8' | luac -l -

main <stdin:0,0> (3 instructions, 12 bytes at 0x8982b30)
0+ params, 2 slots, 0 upvalues, 0 locals, 1 constant, 0 functions
        1       [1]     LOADK           0 -1    ; 256
        2       [1]     RETURN          0 2
        3       [1]     RETURN          0 1


> Generally: nice, luaish peace of code.
> 
> The tricky module-mechanism is not easy to
> understand. I mean things like this
> 
>      local name = (...):gsub('%.[^%.]+$', '')
>      local read = require (name..".read")
> 
> and similar lines.

I'm not actually entirely happy with that; it feels ugly and slightly
hackish. I have yet to come up with a better way, though.

> Wouldn't it be worthwhile to explain this idiom and
> put it as a "Lua-Mini-Gem" to the Wiki?
> (while we are waiting for the Lua Gemas ;-)

There's a thought. NameIndependentModules, perhaps?

	Ben Kelly