Error handling is primary source is absent

Hi Artur,

Your issue is with File.Contents: It gets an error trying to access the file but transforms this error into a binary anyway. So, when try is executed it gets a value but without errors, since the error is inside this value.
Since error are transferable, I'm not sure how this happens.
It is -- for me -- a bug of the pqengine evaluation system.

Aaaaanyway,

Try using file.contents alone, something like:

Source = try (try File.Contents(filestring1))[Value]{0},
Source_final = if Source[HasError] then File.Contents(filestring2) else File.Contents(filestring1)
Nah, I actually tested this. It won't work since the error is still inside the binary. It happens on accessing it. This will work:

Source = try Binary.Length((try File.Contents(filestring1))[Value])

Source_final = if Source[HasError] then File.Contents(filestring2) else File.Contents(filestring1)

And then apply the csv transformations


Edit2: You could also simplify step1 as :
try Binary.Length(File.Contents(filestring1))