[Chicken-janitors] [Chicken-bugs] #331: Unit utils: Inconsistent behavior of procedures shift! & unshift!

[Chicken Scheme]

#331: Unit utils: Inconsistent behavior of procedures shift! & unshift!
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 Reporter:  Jon Strait <address@hidden>  |       Type:  defect
   Status:  new                                |   Priority:  minor 
Component:  core libraries                     |    Version:  2.7   
 Keywords:                                     |  
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 Currently shift! on a list with one element throws an error about setting
 the list to the empty list and it not being a pair.  However, shift! on an
 empty list returns #f (for the default value).  If shifting the empty list
 doesn't throw an error, then shifting a one element list shouldn't either.
 Regarding this, I don't see what's conceptually wrong with shifting to the
 empty list or in unshifting the empty list to make a one element list,
 although this may not be standard?  However, the first issue seems really
 inconsistent.

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Ticket URL: <http://trac.callcc.org/ticket/331>
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