[metapost] [graph.mp] bug in gdata?

[Stephan Hennig]

Hi,

in the following file manipulating a variable j or (any?) other variable
inside gdata (from graph.mp) works fine.  Except for variable i.  That
variable throws and error in MetaPost v0.901.  A bug?

Best regards,
Stephan Hennig

input graph
beginfig(1);
numeric i, j;
  j := 0;
  gdata("test.dat", v, j:=j+1; );%%% Works.
%   i := 0;
%   gdata("test.dat", v, i:=i+1; );%%% Fails.
endfig;
end

Instead of "test.dat" you can take any file name of a text file, e.g.,
the MetaPost source file name itself.