\d h
\l a
\l t
\l x

comb:{apply@(type comb21[two@$**X]@)'Tokens comb12[two@$**X]x}
two:{x@&1<#:'x}
comb21:{(x,,y)((2#*:)'x)?y}
comb12:{_ssr/[y;{:["*"=x 1;x[0],"[*]";x]}'x;(2#*:)'x]}
apply:{*(pair .)/(();x)}
pair:{:[~#y;(x;y);~`"("~*y;(:[#x;({};x;*y);*y];1_ y);(({};x;apply 1_ i#y);((1+i:group y)_ y))]}
group:{(=/+\'x~\:/:`$'"()")?1}

N:"0123456789"
num:{(x[0]_in"-.",N)&|/N _lin x}
V:".-_~!@#$%^&*=+|<,>?"
A:"/\\'"
A_:$`converge`Converge`loop`Loop
system:{x _in $`cond`cons`head`tail`eq}
verb:{(x[0]_in V)&1=#x}
project:{[x](x[0]_in V)&"."=*1_ x}
unary:{(x[0]_in V)&":"=*1_ x}
adverb:{(x _in 2#A_)|(x[0]_in A)&(1=#x)|:[2=#x;":"=*1_ x;0]}
binary:{(x _in 2_ A_)|(x[0]_in A)&:[1<#x;"."=x 1;0]}
combinator:{(_ic[*x]_in 65+!26)&:[1<#x;&/(1_ x)_lin"'*";1]}
sym:{atom`$1_'(&x="`")_ x}
atom:{:[1=#x;*x;x]}

type:{
 :[x[0]_in"()"          ;`$*x
   "nil"~x              ;({`n};())
   "null"~x             ;({`n};)
   "nan"~x              ;({`n};0n)
   "Nan"~x              ;({`n};0N)
   "inf"~x              ;({`n};0i)
   "Inf"~x              ;({`n};0I)
   "`"=*x               ;({`n};sym x)
   "\""=*x              ;({`n};. x)
   system x             ;. 1!"}{`",x
   combinator x         ;`$x
   num x                ;({`n};. x)
   verb x               ;({`v};. x)
   project x            ;({`v};.-1!x,"[;x]}{")
   unary x              ;({`u};. x)
   adverb x             ;({`a};. A1 x)
   binary x             ;({`b};. A2 x)
                         `$x]}

\d ^
Comb:h.comb