modernc.org/knuth@v0.0.4/web/testdata/ctan.org/tex-archive/systems/knuth/dist/texware/pooltype.ch (about)

     1  @x
     2  @d abort(#)==begin write_ln(#); goto 9999;
     3  @y
     4  @d write_ln(#)==writeln(#)
     5  @d read_ln(#)==readln(#)
     6  @d abort(#)==begin write_ln(#); goto 9999;
     7  @z