myprintsep(s,v[..])=if(#v>0,print1(v[1]);for(i=2,#v,print1(s,v[i])));print();
print(myprintsep)
?myprintsep
arity(myprintsep)
print1(":");myprintsep()
print1(":");myprintsep(", ")
myprintsep(", ",a,b,c,d)
myprintsep(", ",a,,c,)
myprintsep(,a,b,c,d)

myprintf = printf;
myprintf("x=%d\n",5)
myprintf("x=%d y=%d\n",5,7)
myprintf("x=%d y=%d z=%d\n",5,7,9)

f1(x,y=0)=x+y;
arity(f1)
arity(()->1)

default(strictargs,1)
myprintsep(s,v[..])=if(#v>0,print1(v[1]);for(i=2,#v,print1(s,v[i])));print();
arity(myprintsep)
print1(":");myprintsep()
print1(":");myprintsep(", ")
myprintsep(", ",a,b,c,d)
myprintsep(,a,b,c,d)
myprintsep(", ",a,,c,)
make_function(a) = (b,c)->123;
f=make_function(456);
f(1)
