Unable to get a resource of type

Error message

Unable to get a resource of type {} from {path:?}! The resource has no associated loader for its extension and its actual data has some other data type!

What it means

ResourceManager::find<T>(path) only returns resources whose data type matches T. When there is no loader whose extension maps to T and the already-loaded resource at that path holds a different data type, the manager cannot satisfy the typed lookup and panics, including T's type UUID.

Solutions

Use the correct type parameter matching the loader/extension registered for the path.
Call find untyped (UntypedResource) if you need whatever resource exists at the path regardless of type.
Register a loader for that extension/type in ResourceManagerBuilder so is_extension_matches_type::<T> succeeds.
Fix the file extension or the path so it matches the intended resource type.

Example fix

// before
let texture = resource_manager.find::<Texture>("data/model.fbx")?; // wrong type for ext
// after
let model = resource_manager.find::<Model>("data/model.fbx")?;

Defensive patterns

Strategy: validation

Validate before calling

// verify extension maps to the requested type before find::<T>
let ext = path.extension().and_then(|e| e.to_str()).unwrap_or("");
debug_assert_eq!(ext, "png", "texture path expected");
let _ = resource_manager.find::<Texture>(path.clone()); // in dev builds

Try / catch

// panics are not catchable safely; use untyped lookup then downcast
let untyped = resource_manager.find(path);
if untyped.type_uuid() == Texture::type_uuid() { /* safe to use as Texture */ }

Prevention

Match the generic type to the file extension's registered loader.
Use untyped find + type_uuid check when the type is uncertain.
Register all custom loaders centrally in one builder function.
Avoid reusing one path for multiple resource types.

When it happens

Trigger: Calling resource_manager.find::<T>(path) where path's extension has no registered loader for T and the cached untyped resource at that path was loaded as a different type (e.g. find::<Texture>("foo.png") when foo.png is registered/loaded as something else, or extension maps to another type).

Common situations: Copying paths between typed resource managers (texture vs. model vs. sound); renaming a file to a wrong extension; expecting a generic loader for an unusual extension; type parameters swapped after refactors.

Understand the failure class

Background: Type mismatch errors: IllegalArgumentException, TypeError and type guards across 150 open-source libraries — this error's family across 150 libraries.

Related errors

AI-assisted analysis of FyroxEngine/Fyrox@76c91aad8e (2026-09-10). Data as JSON: /api/errors/999f3035a365fe12. Report an issue: GitHub.

Appendix: source

Thrown at fyrox-resource/src/manager.rs:509

        T: TypedResourceData,
    {
        let path = path.as_ref();
        let mut state = self.state();

        let untyped = state.find(path);

        let data_type_uuid_matches = untyped
            .type_uuid_non_blocking()
            .is_some_and(|uuid| uuid == <T as Reflect>::type_info().type_uuid);

        if !data_type_uuid_matches {
            let has_loader_for_extension = state
                .loaders
                .safe_lock()
                .is_extension_matches_type::<T>(path);

            if !has_loader_for_extension {
                panic!(
                    "Unable to get a resource of type {} from {path:?}! The resource has no \
                    associated loader for its extension and its actual data has some other \
                    data type!",
                    <T as Reflect>::type_info().type_uuid,
                )
            }
        }

        Resource {
            untyped,
            phantom: PhantomData::<T>,
        }
    }

    /// Find the resource for the given UUID without loading the resource.
    /// If the resource is not already loading, then it will be returned in
    /// the [`ResourceState::Unloaded`] state, and [`Self::request_resource`] may
    /// be used to begin the loading process.

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