Jaction

This isolation enables safe parallel execution where each handle operates on its own task snapshot.

Return Types

JActionExecution (returned by Execute, awaited from ExecuteAsync):

• .Action - The JAction that was executed
• .Cancelled - Whether THIS specific execution was cancelled
• .Executing - Whether the action is still executing
• .Dispose() - Returns JAction to pool

JActionExecutionHandle (returned by ExecuteAsync before await):

• .Action - The JAction being executed
• .Cancelled - Whether this execution is cancelled
• .Executing - Whether still running
• .Cancel() - Cancel THIS specific execution
• .AsUniTask() - Convert to UniTask<JActionExecution>
• Awaitable: await handle returns JActionExecution

API Reference

Execution

Actions

Timing

Loops

All loop methods have <TState> overloads for zero-allocation with reference types.

Configuration

Static Members

Patterns

Basic Sequence

using var result = await JAction.Create()
    .Do(static () => Debug.Log("Step 1"))
    .Delay(1f)
    .Do(static () => Debug.Log("Step 2"))
    .ExecuteAsync();

Always Use using var (CRITICAL)

// CORRECT - auto-disposes and returns to pool
using var result = await JAction.Create()
    .Do(() => LoadAsset())
    .WaitUntil(() => assetLoaded)
    .ExecuteAsync();

// WRONG - memory leak, never returns to pool
await JAction.Create()
    .Do(() => LoadAsset())
    .ExecuteAsync();

Parallel Execution with Per-Execution Cancellation

var action = JAction.Create()
    .Parallel()
    .Do(static () => Debug.Log("Start"))
    .Delay(5f)
    .Do(static () => Debug.Log("Done"));

// Start multiple concurrent executions (each gets own task snapshot)
var handle1 = action.ExecuteAsync();
var handle2 = action.ExecuteAsync();

// Cancel only the first execution
handle1.Cancel();

// Each has independent Cancelled state
var result1 = await handle1;  // result1.Cancelled == true
var result2 = await handle2;  // result2.Cancelled == false

action.Dispose();

UniTask.WhenAll with Parallel

var action = JAction.Create()
    .Parallel()
    .Delay(1f)
    .Do(static () => Debug.Log("Done"));

var handle1 = action.ExecuteAsync();
var handle2 = action.ExecuteAsync();

await UniTask.WhenAll(handle1.AsUniTask(), handle2.AsUniTask());

action.Dispose();

Zero-Allocation with Reference Types

// CORRECT - static lambda + reference type state = zero allocation
var data = new MyData();
JAction.Create()
    .Do(static (MyData d) => d.Process(), data)
    .Execute();

// Pass 'this' when inside a class - no wrapper needed
public class Enemy : MonoBehaviour
{
    public bool IsStunned;

    public void ApplyStun(float duration)
    {
        IsStunned = true;
        JAction.Create()
            .Delay(duration)
            .Do(static (Enemy self) => self.IsStunned = false, this)
            .ExecuteAsync().Forget();
    }
}

// Value types use closures (boxing would defeat zero-alloc anyway)
int count = 5;
JAction.Create()
    .Do(() => Debug.Log($"Count: {count}"))
    .Execute();

Timeout Handling

using var result = await JAction.Create()
    .WaitUntil(() => networkReady)
    .ExecuteAsync(timeout: 30f);

if (result.Cancelled)
    Debug.Log("Timed out!");

Cancellation Callback

var action = JAction.Create()
    .OnCancel(() => Debug.Log("Cancelled!"))
    .Delay(10f);

var handle = action.ExecuteAsync();
handle.Cancel();  // Triggers OnCancel callback

Game Patterns

Cooldown Timer

public class AbilitySystem
{
    public bool CanUse = true;

    public async UniTaskVoid TryUseAbility(float cooldown)
    {
        if (!CanUse) return;
        CanUse = false;

        PerformAbility();

        // Pass 'this' as state - no extra class needed
        using var _ = await JAction.Create()
            .Delay(cooldown)
            .Do(static s => s.CanUse = true, this)
            .ExecuteAsync();
    }
}

Damage Over Time

public sealed class DoTState
{
    public IDamageable Target;
    public float DamagePerTick;
}

public static async UniTaskVoid ApplyDoT(
    IDamageable target, float damage, int ticks, float interval)
{
    var state = JObjectPool.Shared<DoTState>().Rent();
    state.Target = target;
    state.DamagePerTick = damage;

    using var _ = await JAction.Create()
        .Repeat(
            static s => s.Target?.TakeDamage(s.DamagePerTick),
            state, count: ticks, interval: interval)
        .ExecuteAsync();

    state.Target = null;
    JObjectPool.Shared<DoTState>().Return(state);
}

Wave Spawner

public async UniTask RunWaves(WaveConfig[] waves)
{
    foreach (var wave in waves)
    {
        using var result = await JAction.Create()
            .Do(() => UI.ShowWaveStart(wave.Number))
            .Delay(2f)
            .Do(() => SpawnWave(wave))
            .WaitUntil(() => ActiveEnemyCount == 0, timeout: 120f)
            .Delay(wave.DelayAfter)
            .ExecuteAsync();

        if (result.Cancelled) break;
    }
}

Health Regeneration

public sealed class RegenState
{
    public float Health, MaxHealth, HpPerTick;
}

public static async UniTaskVoid StartRegen(RegenState state)
{
    using var _ = await JAction.Create()
        .RepeatWhile(
            static s => s.Health = MathF.Min(s.Health + s.HpPerTick, s.MaxHealth),
            static s => s.Health < s.MaxHealth,
            state, frequency: 0.1f)
        .ExecuteAsync();
}

Troubleshooting

Common Mistakes

1. Missing using var - Memory leak, JAction never returns to pool
2. Using Execute() in production - Blocks main thread, causes frame drops
3. State overloads with value types - Causes boxing; use closures instead
4. Forgetting Execute/ExecuteAsync - Nothing happens
5. Heavy work in .Do() - Callbacks run atomically; keep them lightweight
6. Using action.Cancel() in parallel - Cancels ALL executions; use handle.Cancel() for specific execution
7. Modifying JAction after ExecuteAsync - Changes don't affect running execution (task snapshot isolation)