start rework design

Cargo.toml

@@ -20,3 +20,4 @@ serde = {version = "1.0.126", features = ["derive"]}
 serde-lexpr = "0.1.2"
 serde_cbor = "0.11.1"
 serde_json = "1.0.64"
+smallbox = "0.8.0"

src/ext.rs

@@ -0,0 +1,3 @@
+use super::*;
+
+pub use object::ObjectExt;

src/formats.rs

@@ -1,41 +1,32 @@
 //! The available formats to convert
 use super::*;
-use processor::Processor;
+use std::io;
+use object::{
+    Object, OwnedObject,
+};
 
-/// All formats and their associated processor
-pub enum Format
+pub struct Config;
+
+/// A directive for a format on how to encode and decode objects.
+#[derive(Clone, Copy)]
+pub struct FormatDirective
 {
-    Json(processor::Json),
-    SExpr(processor::Sexpr),
-    CBor(processor::Cbor),
+    encode: fn (&Config, &mut dyn io::Write, &dyn Object) -> io::Result<usize>,
+    decode: fn (&Config, &mut dyn io::Read) -> io::Result<(OwnedObject<'static>, usize)>,
 }
 
-impl Format
-{
-    /// The processor for this format
-    pub fn processor(&self) -> &(dyn Processor + 'static)
-    {
-	match &self {
-	    Self::Json(a) => a,
-	    Self::SExpr(a) => a,
-	    Self::CBor(a) => a,
-	}
-    }
-    
-    /// The processor for this format
-    pub fn processor_mut(&mut self) -> &mut (dyn Processor + 'static)
-    {
-	match self {
-	    Self::Json(a) => a,
-	    Self::SExpr(a) => a,
-	    Self::CBor(a) => a,
-	}
-    }
+macro_rules! directive {
+    ($($name:literal),+ => $encode:expr, $decode:expr) => {
+	(&[$($name),+], FormatDirective {
+	    encode: $encode,
+	    decode: $decode,
+	})
+    };
 }
 
-/// All format objects and their name(s)
-pub static FORMATS: &[(&'static [&'static str], Format)] = &[
-    (&["json"], Format::Json(processor::Json)),
-    (&["s-expression", "sexpr"], Format::SExpr(processor::Sexpr)),
-    (&["cbor"], Format::CBor(processor::Cbor)),
+/// All format directives and their name(s)
+pub static FORMATS: &[(&'static [&'static str], FormatDirective)] = &[
+    directive!("json" => |_, _, _| todo!(), |_, _| todo!()),
+    directive!("s-expression", "sexpr" => |_, _, _| todo!(), |_, _| todo!()),
+    directive!("cbor" => |_, _, _| todo!(), |_, _| todo!()),
 ];

src/lib.rs

@@ -1,7 +1,9 @@
 
 #![allow(dead_code)]
 
-mod processor;
+mod ext; use ext::*;
+
+mod object;
 mod formats;
 
 #[cfg(test)]

src/object.rs

@@ -0,0 +1,29 @@
+use super::*;
+use smallbox::{
+    SmallBox,
+    space,
+    smallbox,
+};
+
+type OwnedObjectStackSize = space::S4;
+
+/// An object that can be expose serialise+deserialise methods
+pub trait Object{
+    // TODO
+}
+
+/// A polymorphic `Object` that is owned.
+pub type OwnedObject<'a> = SmallBox<dyn Object + 'a, OwnedObjectStackSize>;
+
+pub trait ObjectExt<'a>: Sized
+{
+    fn into_owned(self) -> OwnedObject<'a>;
+}
+
+impl<'a, T: 'a> ObjectExt<'a> for T
+where T: Object
+{
+    #[inline] fn into_owned(self) -> OwnedObject<'a> {
+	smallbox!(self)
+    }
+}

src/processor.rs

@@ -1,89 +0,0 @@
-//! Processing
-use super::*;
-use std::io;
-use std::{
-    fmt, error
-};
-
-macro_rules! processor {
-    ($name:ident: {$($body:tt)*}) => {
-	#[derive(Debug)]
-	pub struct $name;
-
-	impl Processor for $name{$($body)*}
-    };
-}
-
-//TODO: Move this to `object.rs`. Have a type that polymorphises any `Serialize` object, somehow...
-//This may be impossible. If it is. Nuke this file, and re-do the `FORMATS` table's value type to `fn(...SOMETHING...) -> io::Result<...SOMETHING...>`
-pub type Object = ();
-
-pub trait Processor
-{
-    //TODO: How to design this trait??? eh...
-    fn read_object(&self, input: &mut dyn io::Read) -> Result<Object, Error>;
-    fn write_object(&self, obj: &Object, output: &mut dyn io::Write) -> Result<usize, Error>;
-}
-
-processor!(Json: {
-    
-});
-processor!(Sexpr: {
-    
-});
-processor!(Cbor: {
-    
-});
-
-#[derive(Debug)]
-enum ErrorKind
-{
-    IO(io::Error),
-    Unknown,
-}
-
-/// Processing error
-pub struct Error(ErrorKind, Option<Box<dyn fmt::Display + 'static>>);
-
-impl fmt::Debug for Error
-{
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result
-    {
-	f.debug_struct("Error")
-	    .field("kind", &self.0)
-	    .field("message_obj", &format_args!("{:?}", self.1.as_ref().map(|x| x.as_ref() as *const _)))
-	    .finish()
-    }
-}
-
-
-impl From<io::Error> for Error
-{
-    #[inline] fn from(from: io::Error) -> Self
-    {
-	Self(ErrorKind::IO(from), None)
-    }
-}
-
-impl error::Error for Error
-{
-    fn source(&self) -> Option<&(dyn error::Error + 'static)> {
-	Some(match &self.0 {
-	    ErrorKind::IO(io) => io,
-	    _ => return None,
-	})
-    }
-}
-
-impl fmt::Display for Error
-{
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result
-    {
-	write!(f, "format processing error")?;
-	if let Some(msg) = self.1.as_ref() {
-	    write!(f, ": {}", msg)
-	} else {
-	    Ok(())
-	}
-    }
-}