config: change default config to use toml-based configuration

toml-config/src/config/spanned.rs

@@ -0,0 +1,63 @@
+use crate::{
+    config::parser::{ParseResult, Parser},
+    toml::{toml_span::Spanned, toml_value::Value},
+};
+
+impl Spanned<&Value> {
+    pub fn parse<P: Parser>(&self, parser: &mut P) -> ParseResult<P> {
+        self.value.parse(self.span, parser)
+    }
+
+    pub fn parse_map<P: Parser, E>(
+        &self,
+        parser: &mut P,
+    ) -> Result<<P as Parser>::Value, Spanned<E>>
+    where
+        <P as Parser>::Error: Into<E>,
+    {
+        self.parse(parser).map_spanned_err(|e| e.into())
+    }
+}
+
+impl Spanned<Value> {
+    pub fn parse<P: Parser>(&self, parser: &mut P) -> ParseResult<P> {
+        self.as_ref().parse(parser)
+    }
+
+    pub fn parse_map<P: Parser, E>(
+        &self,
+        parser: &mut P,
+    ) -> Result<<P as Parser>::Value, Spanned<E>>
+    where
+        <P as Parser>::Error: Into<E>,
+    {
+        self.as_ref().parse_map(parser)
+    }
+}
+
+pub trait SpannedErrorExt {
+    type T;
+    type E;
+
+    fn map_spanned_err<U, F>(self, f: F) -> Result<Self::T, Spanned<U>>
+    where
+        F: FnOnce(Self::E) -> U;
+}
+
+impl<T, E> SpannedErrorExt for Result<T, Spanned<E>> {
+    type T = T;
+    type E = E;
+
+    fn map_spanned_err<U, F>(self, f: F) -> Result<Self::T, Spanned<U>>
+    where
+        F: FnOnce(Self::E) -> U,
+    {
+        match self {
+            Ok(v) => Ok(v),
+            Err(e) => Err(Spanned {
+                span: e.span,
+                value: f(e.value),
+            }),
+        }
+    }
+}