Missing index entry for plt-r6rs

[LiberalArtist]

The plt-r6rs command-line tool documented at:

r6rs/r6rs-doc/r6rs/scribblings/r6rs.scrbl

Lines 74 to 102 in f5e0ddb

	@item{Use the @exec{plt-r6rs} executable, supplying the file that
	contains the program on the command line:
	@commandline{plt-r6rs @nonterm{program-file}}
	Additional command-line arguments are propagated as
	command-line arguments to the program (accessed via
	@racket[command-line]).
	To compile the file to bytecode (to speed future runs of the
	program), use @exec{plt-r6rs} with the @DFlag{compile} flag:
	@commandline{plt-r6rs --compile @nonterm{program-file}}
	The bytecode file is written in a @filepath{compiled}
	sub-directory next to @nonterm{program-file}.
	For example, if @filepath{hi.sps} contains
	@racketblock[
	(import (rnrs))
	(display "hello\n")
	]
	then
	@commandline{plt-r6rs hi.sps}
	prints ``hello.''}

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