clarification for File? and read_tsv(emptyFile)

[antonkulaga]

I think that it should be clarified in the specification that:

1. File? myfile = "does_not_exist" should return null instead of crashing workflow
2. read_tsv(emptyFile) should return Array[Array[String]] as it is what most libs and tools generate when they are provided an empty array/dictionary for tsv generation.

If this is not clarified in some implementations those functions may work fine, while in others lead to workflow_errors.

[cjllanwarne]

I assume your item (1) is referring to outputs from a task (rather than in the middle of a workflow)?

[jdidion]

The section on Files and Optional Outputs addresses #1.

I agree that all of the read_* should have the clarification added that reading from an existing but empty file returns an empty value rather than None.