Modify allpossible stata ado file , so it accepts any number of variables - stata

Question

I am trying to use allpossible.ado to examine the interactions between several variables. It does not accept more than 6 variables. is there a way to modify the code so it accepts any number of variables.
This is the code, This module was written by Nicholas J. Cox
program define allpossible
version 7.0
* process syntax
gettoken cmd 0 : 0
syntax varlist(min=2 numeric ts) [aw fw iw pw] [if] [in] , /*
*/ [ ECLASS(str) RCLASS(str) NPMAX(int -1) * Format(str) /*
*/ CELLWidth(int 12) Detail ]
marksample touse
qui count if `touse'
if r(N) == 0 {
error 2000
}
if "`eclass'`rclass'" == "" {
di as err "must specify at least one of eclass() or rclass()"
exit 198
}
if "`rclass'" != "" {
local nr : word count `rclass'
if `nr' < 2 {
di as err "rclass() invalid"
exit 198
}
tokenize `rclass'
local rprog "qui `1'"
mac shift
local rclass `*'
}
tokenize `varlist'
local response `1'
macro shift
local rest `*'
local np : word count `rest'
local npmax = cond(`npmax' > 0 , min(`npmax',`np', 6), `np')
local nfits = 0
forval i = 0 / `npmax' {
local nfits = `nfits' + comb(`np',`i')
}
qui count
if r(N) < `nfits' {
di as err "sorry: # of observations should be at least `nfits'"
exit 198
}
* wire in response and apply any weights
local cmd "`cmd' `response'"
if "`detail'" != "" {
local cmd "noisily `cmd'"
}
local etc "[`weight' `exp'] if `touse', `options'"
* main loop, except that we break out somewhere before repetition
qui while 1 {
* no predictors
`cmd' `etc'
foreach s of local eclass {
tempvar v`s'
gen double `v`s'' = e(`s') in 1
label var `v`s'' "`s'"
local results "`results'`v`s'' "
}
if "`rclass'" != "" {
`rprog'
foreach s of local rclass {
tempvar v`s'
gen double `v`s'' = r(`s') in 1
label var `v`s'' "`s'"
local results "`results'`v`s'' "
}
}
tempvar predictors model
gen str6 `predictors' = "(none)" in 1
label var `predictors' "predictors"
gen byte `model' = _n
label var `model' "model"
* one predictor
local p = 1
qui forval i = 1 / `np' {
`cmd' ``i'' `etc'
local p = `p' + 1
foreach s of local eclass {
replace `v`s'' = e(`s') in `p'
}
if "`rclass'" != "" {
`rprog'
foreach s of local rclass {
replace `v`s'' = r(`s') in `p'
}
}
replace `predictors' = "`i'" in `p'
}
if `npmax' == 1 {
continue, break
}
* two predictors
local npm1 = `np' - 1
qui forval i = 1 / `npm1' {
local j1 = `i' + 1
forval j = `j1' / `np' {
local p = `p' + 1
`cmd' ``i'' ``j'' `etc'
foreach s of local eclass {
replace `v`s'' = e(`s') in `p'
}
if "`rclass'" != "" {
`rprog'
foreach s of local rclass {
replace `v`s'' = r(`s') in `p'
}
}
replace `predictors' = "`i' `j'" in `p'
}
}
if `npmax' == 2 {
continue, break
}
* three predictors
local npm2 = `np' - 2
qui forval i = 1 / `npm2' {
local j1 = `i' + 1
forval j = `j1' / `npm1' {
local k1 = `j' + 1
forval k = `k1' / `np' {
local p = `p' + 1
`cmd' ``i'' ``j'' ``k'' `etc'
foreach s of local eclass {
replace `v`s'' = e(`s') in `p'
}
if "`rclass'" != "" {
`rprog'
foreach s of local rclass {
replace `v`s'' = r(`s') in `p'
}
}
replace `predictors' = "`i' `j' `k'" in `p'
}
}
}
if `npmax' == 3 {
continue, break
}
* four predictors
local npm3 = `np' - 3
qui forval i = 1 / `npm3' {
local j1 = `i' + 1
forval j = `j1' / `npm2' {
local k1 = `j' + 1
forval k = `k1' / `npm1' {
local l1 = `k' + 1
forval l = `l1' / `np' {
local p = `p' + 1
`cmd' ``i'' ``j'' ``k'' ``l'' `etc'
foreach s of local eclass {
replace `v`s'' = e(`s') in `p'
}
if "`rclass'" != "" {
`rprog'
foreach s of local rclass {
replace `v`s'' = r(`s') in `p'
}
}
replace `predictors' = "`i' `j' `k' `l'" in `p'
}
}
}
}
if `npmax' == 4 {
continue, break
}
* five predictors
local npm4 = `np' - 4
qui forval i = 1 / `npm4' {
local j1 = `i' + 1
forval j = `j1' / `npm3' {
local k1 = `j' + 1
forval k = `k1' / `npm2' {
local l1 = `k' + 1
forval l = `l1' / `npm1' {
local m1 = `l' + 1
forval m = `m1' / `np' {
local p = `p' + 1
`cmd' ``i'' ``j'' ``k'' ``l'' ``m'' `etc'
foreach s of local eclass {
replace `v`s'' = e(`s') in `p'
}
if "`rclass'" != "" {
`rprog'
foreach s of local rclass {
replace `v`s'' = r(`s') in `p'
}
}
replace `predictors' = "`i' `j' `k' `l' `m'" in `p'
}
}
}
}
}
if `npmax' == 5 {
continue, break
}
* six predictors
local npm5 = `np' - 5
quietly forval i = 1 / `npm5' {
local j1 = `i' + 1
forval j = `j1' / `npm4' {
local k1 = `j' + 1
forval k = `k1' / `npm3' {
local l1 = `k' + 1
forval l = `l1' / `npm2' {
local m1 = `l' + 1
forval m = `m1' / `npm1' {
local n1 = `m' + 1
forval n = `n1' / `np' {
local p = `p' + 1
`cmd' ``i'' ``j'' ``k'' ``l'' ``m'' ``n'' `etc'
foreach s of local eclass {
replace `v`s'' = e(`s') in `p'
}
if "`rclass'" != "" {
`rprog'
foreach s of local rclass {
replace `v`s'' = r(`s') in `p'
}
}
replace `predictors' = "`i' `j' `k' `l' `m' `n'" in `p'
}
}
}
}
}
}
if `npmax' == 6 {
continue, break
}
} /* main loop */
* table output
* integers mapped to strings to protect against decimal places
qui foreach v of local results {
capture assert `v' == int(`v')
if _rc == 0 {
tempvar v2
gen str1 `v2' = ""
replace `v2' = string(`v', "%9.0f")
_crcslbl `v2' `v'
local Results "`Results' `v2'"
}
else local Results "`Results' `v'"
}
if "`format'" == "" {
local format "%4.3f"
}
tabdisp `model' in 1 / `p', c(`predictors' `Results') /*
*/ format(`format') cellwidth(`cellwidth')
di
forval i = 1 / `np' {
di as res " `i'" as text "{col 10}``i''"
}
end
I would like to make it able to accept any number of variable.