[comp.text.tex] Files of same TeX codes produce slightly different outputs

xiaofei@acsu.buffalo.edu (Xiaofei Wang) (12/16/90)

Dear TeX users,

I have a strange problem that I find it hard to understand. 

The following two files are actually the same, the only difference is
one has splitted lines and the other joins them together.

But they produce the different outputs. One likes like
 ______
|______ |

The other looks like
 _______
|_______|

By the way, I used emTeX if this is relevent.

Any hint towards understanding of this problem is appreciated. Again
please send me mail even you post on the net. I plan to do some catch up
during holidays. Thanks.

% the 1st file, the same as the 2nd

\font\cs=cmr10 \cs
\magnification=\magstep1
\hbox{
\vrule
{\vbox{\hrule
{\noindent Warning: Do not use 
}
\hrule
}
}
\vrule
}
\end

% the 2nd file, the same as the first
\font\cs=cmr10 \cs
\magnification=\magstep1
\hbox{
\vrule
{\vbox{\hrule
{\noindent Warning: Do not use 
}\hrule}}\vrule}
\end

kesich@acf3.NYU.EDU (John Kesich) (12/18/90)

In TeX, end-of-line, spaces and tabs all count as white-space,
thus the two files you posted are not the same.

Perhaps the following will help illustrate what is different:

% file 1a - same as original file 2
\font\cs=cmr10 \cs
\magnification=\magstep1
\hbox{
\vrule
{\vbox{\hrule
{\noindent Warning: Do not use 
}%
\hrule
}%
}%
\vrule
}
\end

% file 2a - same as original file 1
\font\cs=cmr10 \cs
\magnification=\magstep1
\hbox{
\vrule
{\vbox{\hrule
{\noindent Warning: Do not use 
} \hrule} } \vrule}
\end