(8 may 2003)
||What it does
||(quote mark) Transparency prefix - allows a command to be executed inside another command. Eg 'ZOOM
||(dash) Command line prefix - invokes a non-dialog version of a command. Eg -LAYER
||(underscore) Non-localised command prefix - original English command names in a localised version of AutoCAD. Eg _LINE
||(period) Non-redefined command prefix - of commands that have been messed with by a third party, like PLOT or commands that have been undefined using the UNDEFINE command.
||(plus) Dialog tab prefix - for selecting a particular dialog tab. Eg '._+DSETTINGS
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