[Mondrian] MDX Expression like <Member> <Op> <String> failed

[Julian Hyde]

> I have not exactly understood what kind of testcase I should supply.

When I ask for a testcase I mean a small program that anyone can run, and
reproduces the problem on the foodmart data set.

See the method testUdfToString I added as part of this fix.

> I
> can explain situation when I had a problem. I create function which
> returns <String>:
> 
> <String> AbcTest(...)
> 
> returns one of ('A', 'B', 'C'). And than tried to use in MDX 
> expression
> 
> with
>     member [Measure].[M:Revenue ABC] as 'AbcTest(...)'
> 
>     member [Measure].[M:Revenue] as
>         '[Measure].[Revenue]'
>             , FORMAT = '|#,##0.00|color=' || Iif([Measure].[M:Revenue
> ABC] = 'A', 'red', Iif([Measure].[M:Revenue ABC] = 'B', 'green',
> 'blue'))
> ...
> 
> as result catch exception in log. Because <Member> can not be 
> cast to <String>.

Fixed in change 12851.

Julian