Key Differences - T# versus C#
This page lists everything that is currently not supported in T#
Last updated
This page lists everything that is currently not supported in T#
Last updated
While T# is designed to feel instantly familiar to Unity C# developers, there are a few important differences to keep in mind. These tweaks exist to support the interpreted nature of T# and ensure smoother live editing inside Terra Studio.
Most of your Unity habits will carry over just fine — but for the few edge cases, here's what you need to adjust:
T# follows Unity C# syntax closely, but some common programming patterns and language constructs are not supported due to the interpreted runtime.
✅ Supported: Start(), Update(), typed variables
❌ Not Supported: foreach, switch, enum, inline variable assignment, SerializeField, generics (GetComponent<T>()), etc.
➡️ See Full Syntax Differences in the link below →
T# uses a different base class for networked behavior.
Unity's NetworkBehaviour is replaced by TerraNetBehaviour in T#, and includes its own override methods like OnNetworkSpawn() and OnNetworkDespawn() for multiplayer object lifecycle management.
➡️ See Multiplayer Differences documentation here→
Certain Unity MonoBehaviour APIs are not available in T#, especially those involving advanced lifecycle hooks or reflection.
❌ Not Supported: LateUpdate(), Invoke(), TryGetComponent(), GetComponent<T>(), OnCollisionEnter as coroutine, Start() as coroutine, and more.
✔️ Workaround: Use coroutines manually (StartCoroutine()) and simulate delayed behavior with WaitForSeconds() or WaitForEndOfFrame().
➡️ See Unity API Restrictions here →
T# does not support C# generics-based collections like List<T>, Dictionary<TKey, TValue>, or LINQ queries.
Instead, use Terra-compatible containers:
✅ TerraList
✅ TerraDictionary
❌ Avoid: storing custom scripts or structs in collections
➡️ See Collections & Types restrictions here→
Unity-specific interfaces like IPointerClickHandler, Action with more than 4 parameters, and try-catch blocks are unsupported in T#.
Manual input handling and structured coroutines are your go-to alternatives. Also:
❌ Vector3 boxing
❌ partial classes
✅ PlayerPrefs is fully supported (and integrated with Analytics)
➡️ See Input, UI & Misc Limitations →