MLLP.Envelope.cr
You're seeing just the function
cr, go back to MLLP.Envelope module for more information.
The MLLP Carriage Return character. In documentation it is often represented as <CR>.
The cr is a single-byte character with the ASCII value 0x0D. This character
may appear as "\r" in text editors.
Examples
iex> MLLP.Envelope.eb
<<28>>