Arguments: stream
This is a predicate which returns t if
stream is positioned at the beginning of a line,
else returns nil. It is permissible to always
return nil. This is used in the
implementation of fresh-line. Note that while a value of 0 from
stream-line-column also
indicates the beginning of a line, there are cases where stream-start-line-p can be
meaningfully implemented although stream-line-column can't be. For example, for
a window using variable-width characters, the column number isn't very
meaningful, but the beginning of the line does have a clear
meaning. The default method for stream-start-line-p on class fundamental-character-output-stream uses
stream-line-column, so if
that is defined to return nil, then a method
should be provided for either stream-start-line-p or stream-fresh-line.
See also streams.htm for general information on streams in Allegro CL.
The documentation is described in introduction.htm and the index is in index.htm.
Copyright (c) 1998-2000, Franz Inc. Berkeley, CA., USA. All rights reserved.
Created 2000.10.5.