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(groff)Parameters

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Enter node , (file) or (file)node

Parameters
----------

   The arguments to a macro can be examined using a variety of escapes.
The number of arguments is available in the `.$' number register.  Any
individual argument can be retrieved with one of the following escapes:

 - Escape: \$n
 - Escape: \$(NN
 - Escape: \$[NNN]
     The escapes `\$N', `\$(NN' and `\$[NNN]' retrieve the Nth, NNth or
     NNNth argument.  As usual, the first form only accepts a single
     number (larger than zero), the second a two-digit number (larger
     or equal to 10), and the third any positive integer value (larger
     than zero).  Macros can have an unlimited number of arguments.
     Note that due to copy-in mode, use two backslashes on these in
     actual use to prevent interpolation until the macro is actually
     invoked.

 - Request: .shift [n]
     Shifts the arguments 1 position, or as many positions as specified
     by its argument.  After executing this request, argument I becomes
     argument I-N; arguments 1 to N are no longer available.  Shifting
     by negative amounts is currently undefined.

 - Escape: \$*
 - Escape: \$@
     In some cases it is convenient to use all of the arguments at once
     (for example, to pass the arguments along to another macro).  The
     `\$*' escape concatenates all the arguments separated by spaces.  A
     similar escape is `\$@', which concatenates all the arguments with
     each surrounded by double quotes, and separated by spaces.

 - Escape: \$0
     The name used to invoke the current macro.  The `als' request can
     make a macro have more than one name.


          .de vl
          .ie \\n(.$=1 .ds Vl Pre-Release Version
          .el          .ds Vl Version \\$3, \\$4.
          ..

     This would be called as


          .vl $Id: groff.texinfo,v 1.77 2001/05/07 13:36:24 wlemb Exp $


   Note: Request Arguments.