transpose() of single element array - GDL behaviour differs to IDL

[rsiddans]

IDL/GDL transpose() function behaves differently when single element array is passed in:

IDL> a=fltarr(1)
IDL> help,transpose(a)
FLOAT = Array[1]

GDL> a=fltarr(1)
GDL> help,transpose(a)
FLOAT = Array[1, 1]

(I.e. GDL keeps the 2nd 1-element dimension, IDL drops it)

Note that GDL behaves the same as IDL if the argument is 2d but with 1st dimension length=1
(both drop the last dimension):

IDL> a=fltarr(1,2)
IDL> help,transpose(a)
FLOAT = Array[2]

GDL> a=fltarr(1,2)
GDL> help,transpose(a)
FLOAT = Array[2]

[GillesDuvert]

Not only that!
I see also:

IDL> a=findgen(3,7,2,4) &  help,transpose(a,[2,0])       
<Expression>    FLOAT     = Array[2, 3]

GDL> a=findgen(3,7,2,4) &  help,transpose(a,[2,0])
% TRANSPOSE: Incorrect number of elements in permutation.

IDL being very kind with superfluous dimensions.