\DOC WARNING_outstream

\TYPE {WARNING_outstream : TextIO.outstream ref}

\SYNOPSIS
Controlling output stream used when printing {HOL_WARNING}

\KEYWORDS
I/O, messages, output

\DESCRIBE
The value of reference cell {WARNING_outstream} controls where {HOL_WARNING}
prints its argument.

The default value of {WARNING_outstream} is {TextIO.stdOut}.

\EXAMPLE
{
- val ostrm = TextIO.openOut "foo";
> val ostrm = <outstream> : outstream

- WARNING_outstream := ostrm;
> val it = () : unit

- HOL_WARNING "Module" "Function" "Sufferin' Succotash!";
> val it = () : unit

- TextIO.closeOut ostrm;
> val it = () : unit

- val istrm = TextIO.openIn "foo";
> val istrm = <instream> : instream

- print (TextIO.inputAll istrm);
<<HOL warning: Module.Function: Sufferin' Succotash!>>
}


\SEEALSO
Feedback, Feedback.HOL_WARNING, Feedback.ERR_outstream, Feedback.MESG_outstream, Feedback.emit_WARNING.
\ENDDOC