fn-format-number first parameter string

[Juan Zacarias]

failing tests 2: numberformat38 numberformat15 numberformat41 numberformat42

First parameter when String should return NaN instead of error, it seems there should be a different way to handle strings as first parameter than just an error

Query
format-number('foo','#############')

Error
Expected result: NaN. Found error XPTY0004 - The query (3f405e36-10f1-4178-9845-b8d485921b4d) evaluated using xqxq:evaluate raised an error at line 9 column 1: The query (96325edb-202b-4f84-8a82-60cfd97fdde6) evaluated using xqxq:evaluate raised an error at line 6 column 1: first parameter to format-number() function is type xs:string that is not allowed