(file-location)
  returns a str or #n
F

Returns a string describing the current file and line number.

For example, (file-location) might return the string "example.glsp:1".

Line numbers are one-indexed: the first line in the file has the index 1.

When the file-location call wasn't parsed from a file, it may not have a corresponding line number at all. In that case, it will return #n.

try-verbose
stack-trace