// dvec.c


// outgoing externals

external[
// Dvec
DefaultArgs1
]


// incoming externals

external[
FrameSize; CallersFrame; Usc; errhlt
]

manifest endCode=#335


// let Dvec(caller, newVecs, nil, nil, nil, nil, nil, nil,
// nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil, nil,
// nil; numargs na)=valof [
//
//let myArgs=lv caller
//let cf=CallersFrame()
//let cfs=FrameSize(caller)
//let top=cf+cfs
//
//let length=0
//let i=0
//while i ls na-1 do [
//i=i+1
//if myArgs!i eq 0 then break
//length=length+rv myArgs!i+1
//rv myArgs!i=top-length
//]
//
//while i ls na-1 do [
//i=i+1
//let t=rv myArgs!i
//if t ge cf & t ls top then rv myArgs!i=t-length
//]
//
//let newCf=cf-length
//if Usc(newCf, rv endCode) le 0 then errhlt("Stack overflow")
//
// BMOVE(cf, newCf, cfs-1)
// resultis newCf+cfs
//let DoMove=table [
//#35003// lda 3 extraArgs,2
//#131400// inc 1 2
//#173000// add 3 2
//#61005// blt
//#121400// inc 1 0return address of first new word
//#35001// lda 3 savedPC,2
//#1401// jmp 1,3
//]
//
//DoMove(cf-1, newCf+cfs-1, -cfs)
//]

let DefaultArgs1(lvNa, base, defaultValue, nil, nil, nil, nil,
nil, nil, nil, nil, nil; numargs na) be [

if na ls 2 then base=0
let defaultOnZero=false
if base ls 0 then [ defaultOnZero=true; base=-base ]

let dvVec=lv defaultValue-base
let actualNumDVs=na-3+base
let defaultDV=(na ls 3 ? 0, dvVec!actualNumDVs)
let callersFormals=CallersFrame()+4

if rv lvNa ls base then errhlt("Too few arguments")

for i=base to (lvNa-callersFormals-1) do
if i ge rv lvNa % (defaultOnZero &
callersFormals!i eq 0) then
callersFormals!i=(i le actualNumDVs ?
dvVec!i, defaultDV)
]