COMIS provides a built-in editor which is automatically
invoked by the interpreter when an error is detected.
The COMIS built-in editor is similar to the
VAX line-mode EDIT/EDT.
A line can be referenced by its line number.
The INSERT
and DELETE
commands change a the line numbering.
To operate on a set of lines it is possible to specify
a line range in the following forms:
N1
to N2
, where
N1<N2
or N1>N2
.
N
-th line from the beginning of the file.
+N
-th line from the current pointer position.
-N
-th line from the current pointer position.
The character ``F
'' is recognized as the first line of the routine and
the character ``L
'' is recognized as its last line; ``W
'' is recognized
as ``F:L
''.