The Text Editor keeps a running log of the changes you make to models in a backup file. If the system crashes, or power is interrupted, or your editing session ends abnormally in some other way, you can use this backup file to recover most of your changes. The recovery is performed the next time you open a file that has a backup in place. If Vensim finds a backup file, it asks you if you want to attempt recovery. If the recovery is successful, you are positioned on the last line that was modified.
The history file is a log of changes you have made to a file, which is added to each time you edit the file. You can specify whether or not you want a history file with the Advanced tab of the Options dialog (use the Tools>Options command).
The format for history and backup files is the same. Lines in each of these files begin with a character to indicate what happened to a line.
! (comment) indicates a comment line.
- (delete) indicates that a line was deleted.
+ (insert) indicates that a line was inserted.
# (line count) displays the number of lines in a file before changes were made.
The first line in a backup file must show the line count # . This number reports how many lines were in the file prior to any changes that were made. The format for a line count is as follows.
This indicates that the file has 314 lines.
-122\This was line 122
This indicates that line 122 (which contained the text " This was line 122") was removed from the file.
+122\This is the new line 122
This indicates that a new line containing the text "This is the new line 122" was inserted before line 122.
This indicates that line 117 was changed from ":GARPH test-graph-1" to ":GRAPH test-graph-1"