dellingr 0.4.0

An embeddable, pure-Rust Lua VM with precise instruction-cost accounting
Documentation 
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-- Historical probe, kept as the regression tracker for its fix. Until
-- 2026-07-26 every Lua call re-interned ALL of the callee chunk's string
-- literals and truncated them on return - cost proportional to the literal
-- count, not to what the call touched. `classify` carries ~32 distinct
-- string constants but returns from the first branch, so that interning was
-- pure per-call overhead. The per-(State, Bytecode) literal cache (commit
-- b14fde8) collapsed the seconds-scale twin bench/many_literals.lua from
-- 5.0s to 0.7s (interleaved worktree pairs, plantasjen); this file now
-- guards against the per-call path ever coming back.
-- Compare against calls/local.lua: same local-call shape, one literal.

local function classify(code)
    if code == 0 then return "ok" end
    if code == 1 then return "err_perm" end
    if code == 2 then return "err_noent" end
    if code == 3 then return "err_srch" end
    if code == 4 then return "err_intr" end
    if code == 5 then return "err_io" end
    if code == 6 then return "err_nxio" end
    if code == 7 then return "err_2big" end
    if code == 8 then return "err_noexec" end
    if code == 9 then return "err_badf" end
    if code == 10 then return "err_child" end
    if code == 11 then return "err_again" end
    if code == 12 then return "err_nomem" end
    if code == 13 then return "err_acces" end
    if code == 14 then return "err_fault" end
    if code == 15 then return "err_notblk" end
    if code == 16 then return "err_busy" end
    if code == 17 then return "err_exist" end
    if code == 18 then return "err_xdev" end
    if code == 19 then return "err_nodev" end
    if code == 20 then return "err_notdir" end
    if code == 21 then return "err_isdir" end
    if code == 22 then return "err_inval" end
    if code == 23 then return "err_nfile" end
    if code == 24 then return "err_mfile" end
    if code == 25 then return "err_notty" end
    if code == 26 then return "err_txtbsy" end
    if code == 27 then return "err_fbig" end
    if code == 28 then return "err_nospc" end
    if code == 29 then return "err_spipe" end
    if code == 30 then return "err_rofs" end
    return "unknown"
end

function _bench()
    local hits = 0
    for i = 1, 1000 do
        if classify(0) == "ok" then
            hits = hits + 1
        end
    end
    return hits
end

for i = 1, 700 do _bench() end
print("calls/many_literals: true")