SourcePos package:ginger
The abstract data type
SourcePos represents source positions.
It contains the name of the source (i.e. file name), a line number and
a column number.
SourcePos is an instance of the
Show,
Eq and
Ord class.
withSourcePos pos action runs action in a context
where the current source location is set to pos. The original
source position is restored when action finishes.