Squashed 'vendor/ruvector/' content from commit b64c2172

git-subtree-dir: vendor/ruvector
git-subtree-split: b64c21726f2bb37286d9ee36a7869fef60cc6900

crates/ruvector-domain-expansion/src/error.rs

@@ -0,0 +1,39 @@
+//! Error types for domain expansion.
+
+use thiserror::Error;
+
+/// Errors that can occur during domain expansion operations.
+#[derive(Error, Debug)]
+pub enum DomainError {
+    /// Problem generation failed.
+    #[error("problem generation failed: {0}")]
+    Generation(String),
+
+    /// Solution evaluation failed.
+    #[error("evaluation failed: {0}")]
+    Evaluation(String),
+
+    /// Dimension mismatch between domains.
+    #[error("dimension mismatch: expected {expected}, got {got}")]
+    DimensionMismatch { expected: usize, got: usize },
+
+    /// Domain not found in the expansion engine.
+    #[error("domain not found: {0}")]
+    DomainNotFound(String),
+
+    /// Transfer failed between domains.
+    #[error("transfer failed from {source} to {target}: {reason}")]
+    TransferFailed {
+        source: String,
+        target: String,
+        reason: String,
+    },
+
+    /// Kernel has not been trained on any domain yet.
+    #[error("kernel not initialized: {0}")]
+    KernelNotInitialized(String),
+
+    /// Invalid configuration.
+    #[error("invalid config: {0}")]
+    InvalidConfig(String),
+}