update Plane methods and crate examples

- update `Plane` methods to only require a shared reference to `Notcurses`: `from_cli`, `new_at`, `new_sized`, `new_sized_at`.
- update examples: `visual`, `hello-world`, `cli`, `info`, `input`.

examples/cli.rs

@@ -3,7 +3,7 @@
 use notcurses::*;
 
 fn main() -> NotcursesResult<()> {
-    let mut nc = Notcurses::new_cli()?;
+    let nc = Notcurses::new_cli()?;
     let mut cli = nc.cli_plane()?;
 
     putstrln![cli, "{cli:?}"]?;

examples/hello-world.rs

@@ -1,7 +1,7 @@
 use notcurses::*;
 
 fn main() -> NotcursesResult<()> {
-    let mut nc = Notcurses::new_cli()?;
+    let nc = Notcurses::new_cli()?;
     let mut cli = nc.cli_plane()?;
     cli.putstrln("\nhello world!")?;
     cli.render()?;

examples/info.rs

@@ -3,7 +3,7 @@
 use notcurses::*;
 
 fn main() -> NotcursesResult<()> {
-    let mut nc = Notcurses::new_cli()?;
+    let nc = Notcurses::new_cli()?;
     let mut cli = nc.cli_plane()?;
 
     let caps = nc.capabilities();

examples/input.rs

@@ -5,10 +5,10 @@ use std::time::Instant;
 use std::{thread::sleep, time::Duration};
 
 fn main() -> NotcursesResult<()> {
-    let mut nc = Notcurses::new()?;
+    let nc = Notcurses::new()?;
     nc.mice_enable(MiceEvents::All)?;
 
-    let mut plane = Plane::new(&mut nc)?;
+    let mut plane = Plane::new(&nc)?;
     plane.set_scrolling(true);
 
     // blocking

examples/plane.rs

@@ -8,12 +8,12 @@
 use notcurses::*;
 
 fn main() -> NotcursesResult<()> {
-    let mut nc = Notcurses::new_cli()?;
+    let nc = Notcurses::new_cli()?;
 
     // # constructors
 
     // create a root plane at (1, 1), with a child at (2, 2)
-    let mut rootp = Plane::new_at(&mut nc, (1, 1))?;
+    let mut rootp = Plane::new_at(&nc, (1, 1))?;
     let child = rootp.new_child_at((2, 2))?;
 
     // check their position relative to their parent
@@ -29,7 +29,7 @@ fn main() -> NotcursesResult<()> {
     // create a square of Size::new(5, 5) at Position::new(10, 10)
     let size = Size::new(5, 5);
     let top_left = Position::new(10, 10);
-    let p1 = Plane::new_sized_at(&mut nc, size, top_left)?;
+    let p1 = Plane::new_sized_at(&nc, size, top_left)?;
 
     // check top-left and bottom-right square coordinates are inside the plane:
     assert_eq![p1.translate_root(top_left), (Position::new(0, 0), true)];
@@ -44,8 +44,8 @@ fn main() -> NotcursesResult<()> {
     // ...
 
     // # strings
-    // let mut p1 = Plane::new(&mut nc)?;
-    let mut p1 = Plane::new_sized(&mut nc, (4, 4))?;
+    // let mut p1 = Plane::new(&nc)?;
+    let mut p1 = Plane::new_sized(&nc, (4, 4))?;
     p1.set_scrolling(true);
 
     assert_eq!["hello world".len() as u32, p1.putstr("hello world")?];

examples/visual.rs

@@ -14,7 +14,7 @@ const W: u32 = 10;
 const NUMPIX: usize = (H * W) as usize;
 
 fn main() -> NotcursesResult<()> {
-    let mut nc = Notcurses::new_cli()?;
+    let nc = Notcurses::new_cli()?;
 
     // Create a byte buffer with random rgba pixels:
     let mut rng = rand::thread_rng();
@@ -32,19 +32,19 @@ fn main() -> NotcursesResult<()> {
     visual.set_blitter_pixel();
 
     // Blit the visual to a new plane:
-    let mut new_plane = visual.blit(&mut nc)?;
+    let mut new_plane = visual.blit(&nc)?;
     new_plane.render()?;
     sleep(Duration::from_millis(1000));
 
     // Blit the visual to a pre-existing plane:
-    let mut existing_plane = Plane::builder().position((0, 25)).build(&mut nc)?;
-    visual.blit_plane(&mut nc, &mut existing_plane)?;
+    let mut existing_plane = Plane::builder().position((0, 25)).build(&nc)?;
+    visual.blit_plane(&nc, &mut existing_plane)?;
     existing_plane.render()?;
     sleep(Duration::from_millis(1000));
 
     // Blit the visual into a new child plane:
-    let mut parent_plane = Plane::builder().position((10, 50)).build(&mut nc)?;
-    let mut child = visual.blit_child(&mut nc, &mut parent_plane)?;
+    let mut parent_plane = Plane::builder().position((10, 50)).build(&nc)?;
+    let mut child = visual.blit_child(&nc, &mut parent_plane)?;
     parent_plane.render()?;
     // child.render()?;
     sleep(Duration::from_millis(1000));

src/plane/plane.rs

@@ -80,7 +80,7 @@ impl Plane {
     ///
     /// Returns an error if there's already one *cli* plane instantiated.
     #[inline]
-    pub fn from_cli(notcurses: &mut Notcurses) -> Result<Plane> {
+    pub fn from_cli(notcurses: &Notcurses) -> Result<Plane> {
         notcurses.cli_plane()
     }
 
@@ -115,7 +115,7 @@ impl Plane {
     ///
     /// The plane will have the size of the terminal.
     #[inline]
-    pub fn new_at(nc: &mut Notcurses, position: impl Into<Position>) -> Result<Self> {
+    pub fn new_at(nc: &Notcurses, position: impl Into<Position>) -> Result<Self> {
         Self::builder().position(position).build(nc)
     }
 
@@ -124,7 +124,7 @@ impl Plane {
     /// - `size` must be greater than `0` in both dimensions.
     /// - The plane will be positioned at `(0, 0)`.
     #[inline]
-    pub fn new_sized(nc: &mut Notcurses, size: impl Into<Size>) -> Result<Self> {
+    pub fn new_sized(nc: &Notcurses, size: impl Into<Size>) -> Result<Self> {
         Self::builder().size(size).build(nc)
     }
 
@@ -133,7 +133,7 @@ impl Plane {
     /// `size` must be greater than `0` in both dimensions.
     #[inline]
     pub fn new_sized_at(
-        nc: &mut Notcurses,
+        nc: &Notcurses,
         size: impl Into<Size>,
         position: impl Into<Position>,
     ) -> Result<Self> {