Info Catalog groff: Setting Registers groff: Registers groff: Auto-increment

groff: Interpolating Registers

 
 5.6.2 Interpolating Registers
 -----------------------------
 
 Numeric registers can be accessed via the '\n' escape.
 
  -- Escape: \ni
  -- Escape: \n(id
  -- Escape: \n[ident]
      Interpolate number register with name IDENT (one-character name I,
      two-character name ID).  This means that the value of the register
      is expanded in-place while 'gtroff' is parsing the input line.
      Nested assignments (also called indirect assignments) are possible.
 
           .nr a 5
           .nr as \na+\na
           \n(as
               => 10
 
           .nr a1 5
           .nr ab 6
           .ds str b
           .ds num 1
           \n[a\n[num]]
               => 5
           \n[a\*[str]]
               => 6
 

Info Catalog groff: Setting Registers groff: Registers groff: Auto-increment