This ARexx script leaves out icons on the WorkBench for YAM e-mail
messages.  A length-limited version of the message subject is used for the
icon name (special characters are also filtered out).  When a message icon
is double- clicked it opens the e-mail message, launching YAM if it isn't
running.

It does so by creating an ARexx script (with .info file) to open a message,
then it performs a "Leave Out" on the Workbench.  The default link file
location is the YAM program directory.  Note:  most special AmigaDOS
characters in the subject string are replaced with legal ones before
creating the icon name.  Translation strings can be changed, but some
message names may not be legal AmigaDOS file names.  See instructions below
for changing defaults.

Link files can be removed manually, or with the companion script
LvMsgOutClr.  The removal script uses the same algorithm to generate a file
name, but still relies on user verification.

INSTALLATION:
  1) Copy LvMsgOut.yam and LvMsgOutClr.yam to YAM:ARexx/
     Copy Msg_Open.info to YAM: (the YAM program directory)

  2) Check the YAM application path in variable YamApp.  The default value
     is 'YAM:YAM.OS4'

  3) Assign the Rexx scripts to keys in YAM

OPTIONAL:
  4) Change the Rexx file destination variable:
       OpenScrDest = 'YAM:Users/'    /* Message Link Destination        */

  5) Change the Rexx file name length.  Warning: If  message_name.info
     exceeds the system file name length limit the icon file will not be
     created.
       MsgNameLen = 35      /* Max File name length, including .info    */

  6) Change character translation lines at your own risk.  Variable CharsI
     holds characters to be replaced, CharsO holds the replacement
     characters:
       CharsI = ' ,|#?/:<>()[]"' || "'"    /* Characters In             */
       CharsO = '______-{}{}{}`' || "`"    /* Characters Out            */

  7) Enable auto-delete in LvMsgOutClr.yam by un-commenting code at the end.


USAGE:

  Creating message icons:
   - Select a message (only one at a time) and run the script ...
   - [File Requestor]   Verify the file name and path.

  Using "Left Out" Scripts (or not "Left Out" links)
   - Double-click a message icon and the mail message will be opened
   - (YAM will be run if it isn't running).

  Removing "Left Out" Scripts (Put Away)
   The script icon is "Put Away" and the directory contining the script is
   opened on the workbench (the Rexx script is not deleted).
   - Select a message (only one at a time) and run the script ...
   - [File Requestor]   Verify the file name and path.


LIMITATIONS/BUGS:
 - The message icon name may not include AmigaDOS reserved characters
   (LvMsgOut.yam replaces them based on a translation table).
 - The Leave-Out operation fails if the destination directory for the Rexx 
   script has been left-Out on the Workbench.