add support for trait funcs that don't take self

effers-derive/src/lette.rs

@@ -1,26 +1,40 @@
+const LETTERS: &'static str = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+
 #[derive(Clone, Copy)]
 pub struct LettersIter {
-    idx: u32,
+    idx: usize,
 }
 
 impl LettersIter {
     pub fn new() -> Self {
-        Self {
+        Self { idx: 0 }
-            idx: 'A' as u32 - 1,
-        }
     }
 }
 impl Iterator for LettersIter {
-    type Item = char;
+    type Item = String;
 
     fn next(&mut self) -> Option<Self::Item> {
-        for _ in 0..100 {
+        let l = LETTERS.chars().nth(self.idx % LETTERS.len()).unwrap();
-            self.idx += 1;
+        let c = self.idx / LETTERS.len();
-            if let Some(c) = char::from_u32(self.idx) {
-                return Some(c);
-            }
-        }
 
-        None
+        self.idx += 1;
+
+        Some(l.to_string().repeat(c + 1))
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn iter() {
+        let mut i = LettersIter::new();
+
+        assert_eq!(i.next(), Some("A".to_string()));
+        assert_eq!(i.next(), Some("B".to_string()));
+        assert_eq!(i.nth(23), Some("Z".to_string()));
+        assert_eq!(i.next(), Some("AA".to_string()));
+        assert_eq!(i.next(), Some("BB".to_string()));
     }
 }

effers-derive/src/lib.rs

@@ -1,9 +1,13 @@
 use convert_case::{Case, Casing};
+use lette::LettersIter;
 use proc_macro2::{Span, TokenStream};
 use quote::quote;
-use syn::token::{Mut, SelfValue};
+use syn::token::{Dot, Mut, SelfValue};
 use syn::visit_mut::VisitMut;
-use syn::{parse_macro_input, Expr, ExprCall, FnArg, Ident, ItemFn, PathSegment, Receiver};
+use syn::{
+    parse_macro_input, Expr, ExprCall, ExprField, FnArg, Ident, Index, ItemFn, Member, PathSegment,
+    QSelf, Receiver,
+};
 
 mod parse;
 use parse::Args;
@@ -17,6 +21,7 @@ pub fn program(
     item: proc_macro::TokenStream,
 ) -> proc_macro::TokenStream {
     let item = parse_macro_input!(item as syn::ItemFn);
+    // dbg!(&item);
     let mut args = parse_macro_input!(attr as Args);
 
     if args.name.is_none() {
@@ -152,7 +157,7 @@ impl<'a> syn::visit_mut::VisitMut for FuncRewriter<'a> {
         // check if the function name is in args
         // if it is, replace it with the correct name
         if let Expr::Path(path) = &mut *node.func {
-            for (i, effect) in self.args.effects.iter().enumerate() {
+            for ((i, effect), l) in self.args.effects.iter().enumerate().zip(LettersIter::new()) {
                 for func in &effect.functions {
                     let ident = func.alias.clone().unwrap_or(func.ident.clone());
                     if path.path.is_ident(&ident) {
@@ -163,18 +168,61 @@ impl<'a> syn::visit_mut::VisitMut for FuncRewriter<'a> {
                             arguments: syn::PathArguments::None,
                         });
 
+                        let span = [Span::call_site()];
+
                         path.path = effect_path;
 
+                        // qualify the trait se we get
+                        // <A as Printer>::print
+                        // instead of Printer::print
+                        let ty: syn::Type = syn::parse_str(&l).unwrap();
+                        path.qself = Some(QSelf {
+                            lt_token: syn::token::Lt {
+                                spans: span.clone(),
+                            },
+                            ty: Box::new(ty),
+                            position: path.path.segments.len() - 1,
+                            as_token: Some(syn::token::As { span: span[0] }),
+                            gt_token: syn::token::Gt { spans: span },
+                        });
+
+                        // if the effect function takes a self, add it to the list of params
+                        if let Some(mut expr) = func.self_reference.clone() {
                             // then change the parameters so the handler is the first
                             // get the effect's index, and add the inverse num of `.0`s
                             let idx = eff_len - (i + 1);
-                        let m = if func.mut_token.is_some() { "mut " } else { "" };
+
-                        let s = format!("&{}self{}.1", m, ".0".repeat(idx));
+                            for _ in 0..idx {
-                        let expr: Expr = syn::parse_str(&s).unwrap();
+                                expr = Expr::Field(ExprField {
+                                    attrs: vec![],
+                                    base: Box::new(expr),
+                                    dot_token: Dot {
+                                        spans: [Span::call_site()],
+                                    },
+                                    member: Member::Unnamed(Index {
+                                        index: 0,
+                                        span: Span::call_site(),
+                                    }),
+                                });
+                            }
+
+                            expr = Expr::Field(ExprField {
+                                attrs: vec![],
+                                base: Box::new(expr),
+                                dot_token: Dot {
+                                    spans: [Span::call_site()],
+                                },
+                                member: Member::Unnamed(Index {
+                                    index: 1,
+                                    span: Span::call_site(),
+                                }),
+                            });
+
                             node.args.insert(0, expr);
                         }
                     }
                 }
             }
         }
+    }
 }

effers-derive/src/parse.rs

@@ -1,7 +1,7 @@
 use syn::parse::{Parse, ParseStream, Result};
 use syn::punctuated::Punctuated;
 use syn::token::Paren;
-use syn::{parenthesized, Ident, Path, Token};
+use syn::{parenthesized, Expr, ExprPath, ExprReference, Ident, Path, Token};
 
 #[derive(Debug)]
 pub struct Args {
@@ -21,7 +21,7 @@ pub struct Effect {
 pub struct EffectFunction {
     pub ident: Ident,
     pub alias: Option<Ident>,
-    pub mut_token: Option<Token![mut]>,
+    pub self_reference: Option<Expr>,
 }
 
 impl Parse for Args {
@@ -68,14 +68,29 @@ impl Parse for Effect {
 }
 impl Parse for EffectFunction {
     fn parse(input: ParseStream) -> Result<Self> {
-        let mut_token: Option<Token![mut]> = if input.peek(Token![mut]) {
+        let ident = input.parse()?;
-            input.parse()?
+
+        let self_reference: Option<Expr> = if input.peek(Paren) {
+            let content;
+            parenthesized!(content in input);
+
+            // &mut self
+            if content.peek(Token![&]) && content.peek2(Token![mut]) && content.peek3(Token![self])
+            {
+                Some(Expr::Reference(content.parse::<ExprReference>()?))
+            } else
+            // &self
+            if content.peek(Token![&]) && content.peek2(Token![self]) {
+                Some(Expr::Reference(content.parse::<ExprReference>()?))
+            } else if content.peek(Token![self]) {
+                Some(Expr::Path(content.parse::<ExprPath>()?))
+            } else {
+                None
+            }
         } else {
             None
         };
 
-        let ident = input.parse()?;
-
         let alias: Option<Ident> = if input.peek(Token![as]) {
             input.parse::<Token![as]>()?;
             input.parse()?
@@ -86,7 +101,7 @@ impl Parse for EffectFunction {
         Ok(EffectFunction {
             ident,
             alias,
-            mut_token,
+            self_reference,
         })
     }
 }

examples/main.rs

@@ -1,8 +1,10 @@
 use effers::program;
 
-#[program(Smth => Printer(print as p), Logger(mut debug, mut info))]
+#[program(Smth => Printer(print(&self) as p, check as check_printer), Logger(debug(&mut self), info(self)))]
 fn smth(val: u8) -> u8 {
+    if check_printer() {
         p("hey hi hello");
+    }
 
     debug("this is a debug-level log");
     info("this is a info-level log");
@@ -10,7 +12,7 @@ fn smth(val: u8) -> u8 {
     val + 3
 }
 
-#[program(Printer(mut print as p))]
+#[program(Printer(print(&self) as p))]
 fn other_program() {
     p("hey hi hello");
 }
@@ -33,10 +35,11 @@ fn main() {
 
 trait Printer {
     fn print(&self, s: &str);
+    fn check() -> bool;
 }
 trait Logger {
     fn debug(&mut self, s: &str);
-    fn info(&mut self, s: &str);
+    fn info(self, s: &str);
 }
 
 struct IoPrinter;
@@ -44,6 +47,9 @@ impl Printer for IoPrinter {
     fn print(&self, s: &str) {
         println!("{}", s)
     }
+    fn check() -> bool {
+        true
+    }
 }
 
 struct FileLogger;
@@ -51,7 +57,7 @@ impl Logger for FileLogger {
     fn debug(&mut self, s: &str) {
         println!("debug: {}", s)
     }
-    fn info(&mut self, s: &str) {
+    fn info(self, s: &str) {
         println!("info: {}", s)
     }
 }
@@ -66,7 +72,7 @@ impl Logger for NetworkLogger {
             s, self.credentials
         )
     }
-    fn info(&mut self, s: &str) {
+    fn info(self, s: &str) {
         println!(
             "info through network: {}; with password {}",
             s, self.credentials

examples/path.rs

@@ -1,7 +1,7 @@
 use effers::program;
 
 // Effects can be referenced from inside a module
-#[program(inc::Incrementer(increment))]
+#[program(inc::Incrementer(increment(&self)))]
 fn prog(val: u8) -> u8 {
     let x = increment(val);
     let y = increment(x);
@@ -11,10 +11,15 @@ fn prog(val: u8) -> u8 {
 mod inc {
     pub trait Incrementer {
         fn increment(&self, v: u8) -> u8;
+
+        fn check() -> bool;
     }
 
     pub struct TestInc;
     impl Incrementer for TestInc {
+        fn check() -> bool {
+            false
+        }
         fn increment(&self, v: u8) -> u8 {
             v + 3
         }

src/lib.rs

@@ -4,12 +4,12 @@ pub use effers_derive::program;
 mod test {
     use super::*;
 
-    #[program(Smth => Printer(print as p), Logger(mut debug, mut info), inc::Incrementer(mut increment))]
+    #[program(Smth => Printer(print(&self) as p), Logger(debug(self), info(&mut self)), inc::Incrementer(increment))]
     fn smth(val: u8) -> u8 {
         let s = p("hey hi hello");
 
-        debug("this is a debug-level log");
         info("this is a info-level log");
+        debug("this is a debug-level log");
 
         let _s = p("hey hi hello");
 
@@ -24,16 +24,15 @@ mod test {
         fn print(&self, s: &str) -> &str;
     }
     trait Logger {
-        fn debug(&mut self, s: &str);
+        fn debug(self, s: &str);
         fn info(&mut self, s: &str);
     }
     mod inc {
         pub trait Incrementer {
-            fn increment(&mut self, v: u8) -> u8;
+            fn increment(v: u8) -> u8;
         }
     }
 
-    // TODO make nameless programs work
     #[program(Printer(print as p))]
     fn ohter() {
         let _s = p("hey hi hello");