Put all the movement keys together, in order of ascending stride.

Also, move the Undo/Redo keystrokes further up, so that, when the
user has a somewhat wider terminal than the usual 80 characters,
these keystrokes will be shown -- they are far more interesting
than the ^Y and ^V ones, for which PgUp and PgDn can be used.

Since all lines can be partially scrolled off the screen now
(except for edittop, which is forthcoming), the maxlines global
variable and its computation mechanism are no longer needed.

These improvements will eventually make do_home() and do_end() take
parameters.  Since the global function lists can hold only functions
without parameters, preemptively add do_home_void() and do_end_void(),
and make the global function lists use them.

The platform's default char type might be signed, which could cause
problems in 8-bit locales.

This addresses https://savannah.gnu.org/bugs/?50289

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Reported-by: Hans-Bernhard Broeker <HBBroeker@T-Online.de>

Now that we pull in the gnulib regex module, we can assume it exists.

Also, avoid a warning with with --enable-tiny --enable-browser.

In path names and file names, 0x0A means an embedded newline and
should be shown as ^J, but in anything related to the file's data,
0x0A is an encoded NUL and should be displayed as ^@.

So... switch mode at the two main entry points into the "file system"
(reading in a file, and writing out a file), and also when drawing the
titlebar.  Switch back to the default mode in the main loop.

This fixes https://savannah.gnu.org/bugs/?49893.

Also, swap the logic around, to use less braces.

There is no need for a counter, nor an old counter to compare it with.

Instead compute directly whether we're at a softwrapped part or not.

(The variable 'pletion_line' is not conditionalized with this option, as
it would become messy.  The compiler will probably be able to elide it.)

When using --enable-tiny, it is not possible to use --enable-wordcomp,
because the word completion function uses the undo system.

Executing the 'complete_a_word' function will search from the start
of the current buffer for entire words that begin with the fragment
that is before the cursor, and will complete this fragment to the
first word that is found.  Each consecutive call of 'complete_a_word'
will search for the next matching word and will complete the fragment
to that.  By default the function is bound to the ^] keystroke.
Signed-off-by: Sumedh Pendurkar <sumedh.pendurkar@gmail.com>
Signed-off-by: Benno Schulenberg <bensberg@justemail.net>

Reported-by: Sumedh Pendurkar <sumedh.pendurkar@gmail.com>

It can be activated with --linenumbers on the command line or with
'set linenumbers' in a nanorc file, and it can be toggled with M-#.
Signed-off-by: Faissal Bensefia <faissaloo@gmail.com>
Signed-off-by: Benno Schulenberg <bensberg@justemail.net>

Instead of figuring them out from the string.  This is possible
because those dedicated editing keys cannot be rebound anyway.

This fixes https://savannah.gnu.org/bugs/?49058 reported by Rishabh Dave.

And also case-sensitive searches, backward searches, and searching again.

This fixes https://savannah.gnu.org/bugs/?48987.

This fixes https://savannah.gnu.org/bugs/?48988.

Mentioning "GNU nano" instead of "This program" and referring to the
website instead of to a postal address.

Add the keycodes and routines to allow the user to forego setting the
mark explicitly (with M-A / ^6) and instead quickly select a few words
or lines by holding down Shift together with the movement keys.

(Some combinations with Shift are swallowed by some terminal emulators.
To work around some of those, the combinations Shift+Alt+Left/Right work
as Shift+Home/End and Shift+Alt+Up/Down work as Shift+PageUp/PageDown.)

This avoids showing a ghost item in, for example, the WriteOut menu
when not using --tempfile and the user does not bind 'discardbuffer'.

This fixes https://savannah.gnu.org/bugs/?48751 reported by Andrew Ho.

This also fixes compilation when configured with --enable-tiny.

If this breaks your build, please send report or instructions or patch.

This fixes http://savannah.gnu.org/bugs/?48698

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Signed-off-by: Rishabh Dave <rishabhddave@gmail.com>