bendns' repos / rust-analyzer
Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/mbe/src/lib.rs')
-rw-r--r--crates/mbe/src/lib.rs44
1 files changed, 21 insertions, 23 deletions
diff --git a/crates/mbe/src/lib.rs b/crates/mbe/src/lib.rs
index 07b7f4d1a5..6402ceadaa 100644
--- a/crates/mbe/src/lib.rs
+++ b/crates/mbe/src/lib.rs
@@ -67,18 +67,17 @@ impl fmt::Display for ParseError {
#[derive(Debug, PartialEq, Eq, Clone)]
pub enum ExpandError {
+ BindingError(Box<Box<str>>),
+ LeftoverTokens,
+ ConversionError,
+ LimitExceeded,
NoMatchingRule,
UnexpectedToken,
- BindingError(Box<str>),
- ConversionError,
- // FIXME: no way mbe should know about proc macros.
- UnresolvedProcMacro,
- Other(Box<str>),
}
impl ExpandError {
- fn binding_error(e: &str) -> ExpandError {
- ExpandError::BindingError(e.into())
+ fn binding_error(e: impl Into<Box<str>>) -> ExpandError {
+ ExpandError::BindingError(Box::new(e.into()))
}
}
@@ -89,8 +88,8 @@ impl fmt::Display for ExpandError {
ExpandError::UnexpectedToken => f.write_str("unexpected token in input"),
ExpandError::BindingError(e) => f.write_str(e),
ExpandError::ConversionError => f.write_str("could not convert tokens"),
- ExpandError::UnresolvedProcMacro => f.write_str("unresolved proc macro"),
- ExpandError::Other(e) => f.write_str(e),
+ ExpandError::LimitExceeded => f.write_str("Expand exceed limit"),
+ ExpandError::LeftoverTokens => f.write_str("leftover tokens"),
}
}
}
@@ -311,42 +310,41 @@ fn validate(pattern: &MetaTemplate) -> Result<(), ParseError> {
Ok(())
}
+pub type ExpandResult<T> = ValueResult<T, ExpandError>;
+
#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct ExpandResult<T> {
+pub struct ValueResult<T, E> {
pub value: T,
- pub err: Option<ExpandError>,
+ pub err: Option<E>,
}
-impl<T> ExpandResult<T> {
+impl<T, E> ValueResult<T, E> {
pub fn ok(value: T) -> Self {
Self { value, err: None }
}
- pub fn only_err(err: ExpandError) -> Self
+ pub fn only_err(err: E) -> Self
where
T: Default,
{
Self { value: Default::default(), err: Some(err) }
}
- pub fn str_err(err: String) -> Self
- where
- T: Default,
- {
- Self::only_err(ExpandError::Other(err.into()))
+ pub fn map<U>(self, f: impl FnOnce(T) -> U) -> ValueResult<U, E> {
+ ValueResult { value: f(self.value), err: self.err }
}
- pub fn map<U>(self, f: impl FnOnce(T) -> U) -> ExpandResult<U> {
- ExpandResult { value: f(self.value), err: self.err }
+ pub fn map_err<E2>(self, f: impl FnOnce(E) -> E2) -> ValueResult<T, E2> {
+ ValueResult { value: self.value, err: self.err.map(f) }
}
- pub fn result(self) -> Result<T, ExpandError> {
+ pub fn result(self) -> Result<T, E> {
self.err.map_or(Ok(self.value), Err)
}
}
-impl<T: Default> From<Result<T, ExpandError>> for ExpandResult<T> {
- fn from(result: Result<T, ExpandError>) -> Self {
+impl<T: Default, E> From<Result<T, E>> for ValueResult<T, E> {
+ fn from(result: Result<T, E>) -> Self {
result.map_or_else(Self::only_err, Self::ok)
}
}