[GHC] #16089: seq is not cooperating with :sprint in GHCi as expected

[GHC]

#16089: seq is not cooperating with :sprint in GHCi as expected
-------------------------------------+-------------------------------------
        Reporter:  radrow            |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  normal            |            Milestone:
       Component:  GHCi              |              Version:  8.6.3
      Resolution:                    |             Keywords:  seq sprint
                                     |  strictness
Operating System:  Linux             |         Architecture:
 Type of failure:  Incorrect result  |  Unknown/Multiple
  at runtime                         |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
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Comment (by radrow):

 Replying to [comment:1 osa1]:
 > I can't reproduce this:
 >
 > {{{
 > GHCi, version 8.6.3: http://www.haskell.org/ghc/  :? for help
 > Loaded GHCi configuration from /home/omer/rcbackup/.ghci
 > λ:1> let x = [True, False]
 > λ:2> :sprint x
 > x = [True,False]
 > }}}
 >
 > With 8.4.4:
 >
 > {{{
 > GHCi, version 8.4.4: http://www.haskell.org/ghc/  :? for help
 > Loaded GHCi configuration from /home/omer/rcbackup/.ghci
 > λ:1> let x = [True, False]
 > λ:2> :sprint x
 > x = [True,False]
 > }}}
 >
 > With 8.2.2:
 >
 > {{{
 > GHCi, version 8.2.2: http://www.haskell.org/ghc/  :? for help
 > Loaded GHCi configuration from /home/omer/rcbackup/.ghci
 > λ:1> let x = [True, False]
 > λ:2> :sprint x
 > x = [True,False]
 > }}}
 >
 > However if I use a list that is not completely static then I can see
 that `:sprint` doesn't print the evaluated constructor:
 >
 > {{{
 > GHCi, version 8.6.3: http://www.haskell.org/ghc/  :? for help
 > Loaded GHCi configuration from /home/omer/rcbackup/.ghci
 > λ:1> let x = [1..]
 > λ:2> :sprint x
 > x = _
 > λ:3> x `seq` ()
 > ()
 > λ:4> :sprint x
 > x = _
 > }}}
 >
 > Even `:print` doesn't work as expected (I'd expect it to print something
 like `x : y`):
 >
 > {{{
 > λ:5> :print x
 > x = (_t1::(Num a, Enum a) => [a])
 > }}}

 Note that I am declaring `x` without `let` keyword.
 {{{
 x = [True, False]
 }}}
 not
 {{{
 let x = [True, False]
 }}}

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/16089#comment:2>
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