[execute].
'Command examples:       CHECK|: execute.'.
'                        CHECK|: execute \'replay.cmd\'.'.
''.
'This command redirects input, so that the Checker fetches commands and'.
'replies to queries from a script file instead of from the keyboard.'.
''.
'Ideally, this script file is one which was created by an earlier proof'.
'session with the Checker.  A script file which is created manually is'.
'quite likely to contain slips which may lead to inappropriate actions.'.
''.
'Note that any "errors" in the script file will be faithfully followed:'.
'the script file will be read until the end of the file is reached,'.
'unless some other error forces abandonment of the script.'.
''.
'Nesting of script files is allowed: if during execution of A.CMD, for'.
'instance, a command to execute B.CMD is encountered, control will pass'.
'to B.CMD until the end of this file is reached, at which point control'.
'will revert to A.CMD.  On reaching the end of a script file invoked'.
'interactively (or with the /execute=... command-line switch), control is'.
'returned to the user for further interactive proof work.'.
''.
'If you wish to replay a script from an earlier proof attempt after'.
'making changes to a program\'s assertions, please check that numbering'.
'of hypotheses and conclusions is unaffected.  If this is not the case,'.
'it may also be necessary to edit the script file first to adjust the'.
'hypothesis/conclusion numbers used in commands.'.
