simplek.daul

val A=\m->\x->assert(x,m)val Al=A("len")val At=A("type")val T=\x->type(x)=="table"
val d=\a,f->{val t=[]for(i=1,#a)t[i]=f(i,a[i])t}val c=\x,y->{val t=[]for(i=1,x)t[i]=y[i]t}
val l=\f,x,y->{At(T(x))d(x,\i->f(x[i],y))}val m=\f->\x->if(T(x))l(m(f),x)else f(x)
val r=\f,x,y->{At(T(y))d(y,\i->f(x,y[i]))}val e=\x->T(x)and x or[x]val b=\x->x and 1 or 0
val E=\f,F->\x,y->{[0:\(f(x,y)),l,r,\F->{Al(#x==#y)d(x,\i->F(x[i],y[i]))}][b(T(x))+2*b(T(y))]
 (F and E(f,F)or f,x,y)}val F=\f->E(f,true)val nyi=\(error("nyi"))val env=[]val Ae=A("env")
val S=\x->{if(T(x))("("..table.concat(l(S,x),";")..")")else tostring(x)}val v=["~":m(\x->b(x==0)),
 "!":\x->{At(!T(x))val t=[]for(i=1,x)t[i]=i;t},"@":\x->b(T(x)),"(":\x->x,",":\x->[x],
 "-":m(\x->-x),"%":m(math.sqrt),"_":m(math.floor),"*":\x->if(T(x))x.1 else x,"#":\x->{At(T(x))#x}]
val V=["#":\x,y->{At(!T(x))if(T(y)){Al(x<#y)c(x,y)}else{val t=[]for(i=1,x)t[i]=y;t}},
 "@":\x,y->{At(T(x))r(\t,i->t[i],x,e(y))},",":\x,y->{x=e(x)y=e(y)x=c(#x,x)for(i=1,#y)x[#x+1]=y[i]x},
 "+":F(\x,y->x+y),"-":F(\x,y->x-y),"*":F(\x,y->x*y),"%":F(\x,y->x/y),"!":F(\x,y->y%x)]
val M=["'":\f,x,y->E(f)(x,y),"/":\f,x,y->{for(i=1,#y)x=f(x,y[i])x},"\\":\f,x,y->l(\z->x=f(x,z),y),
 "':":\f,x,y->{val t=[]for(i=1,#y){t[i]=f(x,y[i])x=y[i]}t},"/:":r,"\\:":l]
val N=\s->s.1->sub(s.2,s.2)val n=\s->{val C=N(s)s.2=1+s.2;C}val Ap=A("parse")val Db=\x->{print(x)x}
val P=\s,m,f->{m=[s.1->match("^("..m..")()",s.2)]if(m.1){s.2=m.2;(f or \x->x)(m.1)}}
val p=\s->{val i=P(s,"[a-z]+")val I=P(s,":")var x=v[N(s)]if(i and!I)x=Ae(env[i])else
 x=if(x){n(s)x(p(s))}else P(s,"%d+",tonumber);if(s.2<#s.1){val C=n(s)if(C!=")"){val f=Ap(V[C])
 x=if(!M[N(s)])f(x,p(s))else M[P(s,".:?")](f,x,p(s))}}if(i and I){env[i]=x}x}

while(true){io.write(" ")print(S(p([io.read("*l"),1])))}

// -n negate %n sqrt _n floor #v len !n til @x type ~x not ,x enlist
// x+y add x-y sub x*y mul x%y div x!y mod n#x take v@n at x,y concat
// xF'y each xF/y fold xF\y scan xF':y eachprior xF\:y eachleft xF/:y eachright