diff options
Diffstat (limited to 'nfa/src/error.rs')
| -rw-r--r-- | nfa/src/error.rs | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/nfa/src/error.rs b/nfa/src/error.rs index 0c6bb3c..ad75077 100644 --- a/nfa/src/error.rs +++ b/nfa/src/error.rs @@ -2,10 +2,11 @@ use graph::error::Error as GError; -use std::fmt::{Display, Formatter}; +use core::fmt::{Display, Formatter}; -#[derive(Debug, Clone, Eq, PartialEq, Ord, PartialOrd)] /// The error type for NFA operations. +#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd)] +#[non_exhaustive] pub enum Error { /// An unknown node id is encountered. UnknownNode(usize), @@ -13,8 +14,12 @@ pub enum Error { /// /// Everything is a trade-off, wink wink. UnsupportedOperation, + /// There is no root in the underlying regular expression. + NoRoot, /// This error comes from some underlying graph operation. Graph(GError), + /// A cycle is found when constructing regular expressions. + Cycle, } impl Display for Error { @@ -23,6 +28,8 @@ impl Display for Error { Error::UnknownNode(id) => write!(f, "unknown node: {id}"), Error::UnsupportedOperation => write!(f, "unsupported operation"), Error::Graph(e) => write!(f, "graph error: {e}"), + Error::NoRoot => write!(f, "no root found"), + Error::Cycle => write!(f, "a cycle is found when constructing regular expressions"), } } } |