Vendor dependencies for 0.3.0 release

vendor/wasip2/wit/deps/io/error.wit

@@ -0,0 +1,34 @@
+package wasi:io@0.2.4;
+
+@since(version = 0.2.0)
+interface error {
+    /// A resource which represents some error information.
+    ///
+    /// The only method provided by this resource is `to-debug-string`,
+    /// which provides some human-readable information about the error.
+    ///
+    /// In the `wasi:io` package, this resource is returned through the
+    /// `wasi:io/streams/stream-error` type.
+    ///
+    /// To provide more specific error information, other interfaces may
+    /// offer functions to "downcast" this error into more specific types. For example,
+    /// errors returned from streams derived from filesystem types can be described using
+    /// the filesystem's own error-code type. This is done using the function
+    /// `wasi:filesystem/types/filesystem-error-code`, which takes a `borrow<error>`
+    /// parameter and returns an `option<wasi:filesystem/types/error-code>`.
+    ///
+    /// The set of functions which can "downcast" an `error` into a more
+    /// concrete type is open.
+    @since(version = 0.2.0)
+    resource error {
+        /// Returns a string that is suitable to assist humans in debugging
+        /// this error.
+        ///
+        /// WARNING: The returned string should not be consumed mechanically!
+        /// It may change across platforms, hosts, or other implementation
+        /// details. Parsing this string is a major platform-compatibility
+        /// hazard.
+        @since(version = 0.2.0)
+        to-debug-string: func() -> string;
+    }
+}