@c This is part of the Emacs manual.
-@c Copyright (C) 1985-1987, 1993-1995, 1997, 2000-2013 Free Software
+@c Copyright (C) 1985-1987, 1993-1995, 1997, 2000-2014 Free Software
@c Foundation, Inc.
@c See file emacs.texi for copying conditions.
@node Building
selecting stack frames, and stepping through the program.
@table @kbd
-@item C-x @key{SPC}
-@kindex C-x SPC
+@item C-x C-a C-b
+@kindex C-x C-a C-b
Set a breakpoint on the source line that point is on.
@end table
- @kbd{C-x @key{SPC}} (@code{gud-break}), when called in a source
+ @kbd{C-x C-a C-b} (@code{gud-break}), when called in a source
buffer, sets a debugger breakpoint on the current source line. This
command is available only after starting GUD@. If you call it in a
buffer that is not associated with any debugger subprocess, it signals
The GDB Threads buffer displays a summary of the threads in the
debugged program. @xref{Threads, Threads, Debugging programs with
multiple threads, gdb, The GNU debugger}. To select a thread, move
-point there and type @key{RET} (@code{gdb-select-thread}), or click on
+point there and press @key{RET} (@code{gdb-select-thread}), or click on
it with @kbd{Mouse-2}. This also displays the associated source
buffer, and updates the contents of the other GDB buffers.
@findex load
@findex load-library
+@vindex load-prefer-newer
@cindex load path for Emacs Lisp
If an Emacs Lisp file is installed in the Emacs Lisp @dfn{load path}
(defined below), you can load it by typing @kbd{M-x load-library},
searches through each directory in the Emacs Lisp load path, trying to
find a file matching that library name. If the library name is
@samp{@var{foo}}, it tries looking for files named
-@file{@var{foo}.elc}, @file{@var{foo}.el}, and lastly just
-@file{@var{foo}}; the first one found is loaded. This command prefers
-@file{.elc} files over @file{.el} files because compiled files load
-and run faster. If it finds that @file{@var{lib}.el} is newer than
-@file{@var{lib}.elc}, it issues a warning, in case someone made
+@file{@var{foo}.elc}, @file{@var{foo}.el}, and @file{@var{foo}}. The
+default behaviour is to load the first file found. This command
+prefers @file{.elc} files over @file{.el} files because compiled files
+load and run faster. If it finds that @file{@var{lib}.el} is newer
+than @file{@var{lib}.elc}, it issues a warning, in case someone made
changes to the @file{.el} file and forgot to recompile it, but loads
the @file{.elc} file anyway. (Due to this behavior, you can save
unfinished edits to Emacs Lisp source files, and not recompile until
-your changes are ready for use.)
+your changes are ready for use.) If you set the option
+@code{load-prefer-newer} to a non-@code{nil} value, however, then
+rather than the procedure described above, Emacs loads whichever
+version of the file is newest.
Emacs Lisp programs usually load Emacs Lisp files using the
@code{load} function. This is similar to @code{load-library}, but is
@section Evaluating Emacs Lisp Expressions
@cindex Emacs Lisp mode
@cindex mode, Emacs Lisp
+@cindex evaluation, Emacs Lisp
@findex emacs-lisp-mode
Emacs Lisp mode is the major mode for editing Emacs Lisp. Its mode
The command @kbd{C-x C-e} (@code{eval-last-sexp}) evaluates the
Emacs Lisp expression preceding point in the buffer, and displays the
value in the echo area. When the result of an evaluation is an
-integer, you can type @kbd{C-x C-e} a second time to display the value
-of the integer result in additional formats (octal, hexadecimal, and
-character).
+integer, it is displayed together with the value in other formats
+(octal, hexadecimal, and character).
If @kbd{M-:} or @kbd{C-x C-e} is given a prefix argument, it inserts
the value into the current buffer at point, rather than displaying it
-in the echo area. The argument's value does not matter.
+in the echo area. If the prefix argument is zero, any integer output
+is inserted together with its value in other formats (octal,
+hexadecimal, and character). Such a prefix argument also prevents
+abbreviation of the output according to the variables
+@code{eval-expression-print-level} and @code{eval-expression-print-length}
+(see below).
@kindex C-M-x @r{(Emacs Lisp mode)}
@findex eval-defun
The options @code{eval-expression-print-level} and
@code{eval-expression-print-length} control the maximum depth and
length of lists to print in the result of the evaluation commands
-before abbreviating them. @code{eval-expression-debug-on-error}
-controls whether evaluation errors invoke the debugger when these
-commands are used; its default is @code{t}.
+before abbreviating them. Supplying a zero prefix argument to
+@code{eval-expression} or @code{eval-last-sexp} causes lists to be
+printed in full. @code{eval-expression-debug-on-error} controls
+whether evaluation errors invoke the debugger when these commands are
+used; its default is @code{t}.
@node Lisp Interaction
@section Lisp Interaction Buffers