Singleton list confusion

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Why do Haskell newcomers frequently believe, that list variables must be enclosed in brackets?

People sometimes write argument patterns like

[x]

, hoping that

x

will assume all values of a list successively.

Example:

case xs of
   [x] -> [f x]

although they meant

[f x | x <- xs]

or just

map f xs

It seems like they expect some kind of list comprehension.

However, if there wouldn't be a special list notation and if there wouldn't be the special syntax for the list type constructor (thus we must write

[a]

instead of

List a

then there would be certainly less confusion.

@@ Line 1: / Line 1: @@
 Why do Haskell newcomers frequently believe, that list variables must be enclosed in brackets?
 People sometimes write argument patterns like <hask>[x]</hask>, hoping that <hask>x</hask> will assume all values of a list successively.
-Maybe it is some kind of [[list comprehension]].
+Example:
+<haskell>
+case xs of
+   [x] -> [f x]
+</haskell>
+although they meant
+<haskell>
+[f x | x <- xs]
+</haskell>
+or just <hask>map f xs</hask>.
+It seems like they expect some kind of [[list comprehension]].
+However, if there wouldn't be a special [[list notation]] and if there wouldn't be the special syntax for the list type constructor (thus we must write <hask>[a]</hask> instead of <hask>List a</hask>),
+then there would be certainly less confusion.
+<!-- the first time I saw this in students homework solutions -->
 See for example
-Haskell-Cafe about [http://www.haskell.org/pipermail/haskell-cafe/2008-April/041556.html Pattern match failure]
+Haskell-Cafe about
+[http://www.haskell.org/pipermail/haskell-cafe/2008-April/041496.html testing for same characters in lists of strings],
+[http://www.haskell.org/pipermail/haskell-cafe/2008-April/041556.html Pattern match failure]
 [[Category:Syntax]]