begin work on attr macros

1 files changed, 57 insertions, 0 deletions

diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..bd6ed2b
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,57 @@
+extern crate proc_macro;
+
+use std::path::{Path, PathBuf};
+
+use proc_macro::TokenStream;
+use quote::quote;
+use syn::{parse_macro_input, AttrStyle, Attribute, DeriveInput, Lit, Meta, MetaNameValue};
+
+use serde::{de::DeserializeOwned, Serialize};
+
+trait Config<T>
+where
+    T: Serialize + DeserializeOwned + Default,
+{
+    fn load() -> Result<T, String>;
+    fn store() -> Result<(), String>;
+}
+
+fn is_outer_attribute(a: &Attribute) -> bool {
+    match a.style {
+        AttrStyle::Outer => true,
+        _ => false,
+    }
+}
+
+#[proc_macro_derive(Config, attributes(filename, filetype))]
+pub fn config_attribute(item: TokenStream) -> TokenStream {
+    let mut ast: DeriveInput = syn::parse(item).unwrap();
+
+    let mut filename: Option<PathBuf> = None;
+    let mut filetype: Option<PathBuf> = None;
+
+    for option in ast.attrs.into_iter() {
+        let option = option.parse_meta().unwrap();
+        match option {
+            Meta::NameValue(MetaNameValue {
+                ref path, ref lit, ..
+            }) if path.is_ident("filename") => {
+                if let Lit::Str(f) = lit {
+                    filename = Some(PathBuf::from(f.value()));
+                }
+            }
+            Meta::NameValue(MetaNameValue {
+                ref path, ref lit, ..
+            }) if path.is_ident("filetype") => {
+                if let Lit::Str(f) = lit {
+                    filetype = Some(PathBuf::from(f.value()));
+                }
+            }
+            _ => {}
+        }
+    }
+
+    println!("{:?} {:?}", filename, filetype);
+
+    TokenStream::new()
+}