Fail to parse assignments with pipeline

[blindFS]

Code snippet like this

$a = $a
  | str substring ..3

leads to parsing error because the right hand side is a pipeline instead of expression. This is involved by #28

=====
assignment-003-assignment-to-a-pipeline
=====

$x += 1 | $in + 10
# Note that rhs of ++= is not a pipeline, but only 1
# currently nushell parses this as two statements 
# $x ++= 1 and  $in + 10. Therefore you will get error
# about adding int to nothing, and $x increased by one

-----

(nu_script
  (assignment
    (val_variable
      (identifier))
        (val_number))
    (ERROR)
      (pipeline
        (pipe_element
          (expr_binary
            (val_variable)
            (val_number))))
    (comment)
    (comment)
    (comment)
    (comment))

Since this is no longer the truth, current version of nushell takes 1 | $in + 10 as the rhs value, should we consider to change it back to $.pipeline ?