stride3d/stride · error · InvalidOperationException

Property path parse error: could not find cast operation…

Error message

Property path parse error: could not find cast operation ending ')'

What it means

When compiling an animation property path, a cast segment of the form '(TypeName)Member' is expected to contain a closing parenthesis. UpdateEngine.Compile scans for ')' after the opening '(' and throws InvalidOperationException when none exists, because the cast type name cannot be extracted.

Solutions

1. Inspect the animation path string and add the missing ')' to close the cast, e.g. '[(MyNamespace.MyType)Member]'
2. Verify the full path with a quick check: count '(' vs ')' occurrences before compiling
3. If a cast was not intended, remove the stray '(' from the path
4. Validate path strings when authoring assets so malformed paths fail early in the editor

Example fix

// before
var path = '[(Stride.Rendering.MyComponent)Member'; // missing ')'
// after
var path = '[(Stride.Rendering.MyComponent)Member]';

static bool HasBalancedCast(string path) { int depth = 0; foreach (var c in path) { if (c == '(') depth++; else if (c == ')') depth--; if (depth < 0) return false; } return depth == 0; }
// call before UpdateEngine.Compile: if (!HasBalancedCast(path)) throw new ArgumentException($"Unbalanced cast parens in path: {path}");

try { var compiler = UpdateEngine.Compile(path, type, ...); } catch (InvalidOperationException ex) when (ex.Message.Contains("could not find cast operation")) { // fix/reject malformed path
    throw new ArgumentException($"Malformed animation path '{path}': missing ')'", nameof(path), ex); }

When it happens

Trigger: Calling UpdateEngine.Compile (directly or via AnimationClip compilation) with a property path string containing '(' that opens a cast but has no matching ')' anywhere after it, e.g. '[(MyType)Member' or 'Value((Foo)'.

Common situations: Hand-written animation paths in code or editor data, typos in paths, paths copied partially, or dynamically built path strings that get truncated.

Understand the failure class

Background: "Invalid ... format", "must be in format X", "does not look like a ..." — invalid argument format errors across CLI tools and libraries — this error's family across 17 libraries.

• Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

Related errors

• Property path parse error: could not find indexer end ']'
• Property path parse error: could not parse indexer value
• Property path parse error: could not parse indexer value
• Could not resolve type
• Property path parse error: could not find binding info for…

AI-assisted analysis of stride3d/stride@96fad776d2 (2026-09-14). Data as JSON: /api/errors/f2fa1dcde0f39a9e. Report an issue: GitHub.

Appendix: source

Thrown at sources/engine/Stride.Engine/Updater/UpdateEngine.cs:250

                            throw new InvalidOperationException(string.Format("Property path parse error: could not find binding info for index {0} in type {1}", indexerString, containerType));
                        }

                        ProcessMember(ref state, animationPath, updatableMember, temporaryObjectsList);
                    }
                    else
                    {
                        // Note: first character might be a . delimiter, if so, skip it
                        var propertyStart = state.ParseElementStart;
                        if (animationPath.Name[propertyStart] == PathDelimiter)
                            propertyStart++;

                        // Check if it started with a parenthesis (to perform a cast operation)
                        if (animationPath.Name[propertyStart] == PathCastOpen)
                        {
                            // Parse until end of cast operation
                            state.ParseElementEnd = animationPath.Name.IndexOf(PathCastClose, ++propertyStart);
                            if (state.ParseElementEnd == -1)
                                throw new InvalidOperationException("Property path parse error: could not find cast operation ending ')'");

                            var typeName = animationPath.Name.Substring(propertyStart, state.ParseElementEnd - propertyStart);

                            // Include the indexer close
                            state.ParseElementEnd++;

                            // Try to resolve using alias first, then full assembly registry using assembly qualified name
                            var type = DataSerializerFactory.GetTypeFromAlias(typeName) ?? AssemblyRegistry.GetType(typeName);
                            if (type == null)
                            {
                                throw new InvalidOperationException($"Could not resolve type {typeName}");
                            }

                            // Push entry with new type
                            // TODO: Should we actually perform an early castclass and skip if type is incorrect?
                            state.StackPath.Add(new AnimationBuilderStackEntry(type, state.ParseElementStart, state.ParseElementEnd, -1)
                            {
                                ObjectStartOffset = state.NewOffset,

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