type error corrected (but feels a bit bogus)

altered.wat

(module
  (type (;0;) (func (result i32)))
  (import "env" "__linear_memory" (memory (;0;) 0))
  (func $foo (type 0) (result i32)
    nop
    i32.const 42
    if (result i32)  ;; label = @1
      nop
      i32.const 42
      return
    else
      nop
      i32.const 42
      if (result i32)  ;; label = @2
        nop
        i32.const 42
        return
      else
        nop
        i32.const 42
        if  ;; label = @3
          nop
        else
          nop
          i32.const 42
          if  ;; label = @4
            nop
          else
            nop
          end
          nop
        end
        nop
        i32.const 42
        return
      end
    end))