TransactionService that holds the current transaction state.
Details
It includes a journal that stores non-committed changes to TxRef values and
a retry flag that records whether the transaction should be retried.
Example (Building transactions)
import { Effect } from "effect"
// Transaction class for software transactional memory operations
const txEffect = Effect.gen(function*() {
const tx = yield* Effect.Transaction
// Use transaction for coordinated state changes
return "Transaction complete"
})export class class Transactionclass Transaction {
key: Identifier;
Service: {
retry: boolean;
journal: Map<TxRef<any>, { readonly version: number; value: any }>;
};
}
Service that holds the current transaction state.
Details
It includes a journal that stores non-committed changes to TxRef values and
a retry flag that records whether the transaction should be retried.
Example (Building transactions)
import { Effect } from "effect"
// Transaction class for software transactional memory operations
const txEffect = Effect.gen(function*() {
const tx = yield* Effect.Transaction
// Use transaction for coordinated state changes
return "Transaction complete"
})
Transaction extends import ContextContext.Service<
class Transactionclass Transaction {
key: Identifier;
Service: {
retry: boolean;
journal: Map<TxRef<any>, { readonly version: number; value: any }>;
};
}
Service that holds the current transaction state.
Details
It includes a journal that stores non-committed changes to TxRef values and
a retry flag that records whether the transaction should be retried.
Example (Building transactions)
import { Effect } from "effect"
// Transaction class for software transactional memory operations
const txEffect = Effect.gen(function*() {
const tx = yield* Effect.Transaction
// Use transaction for coordinated state changes
return "Transaction complete"
})
Transaction,
{
retry: booleanretry: boolean
readonly journal: Map<
TxRef<any>,
{ readonly version: number; value: any }
>
interface Map<K, V>Map<
interface TxRef<in out A>TxRef is a transactional value, it can be read and modified within the body of a transaction.
When to use
Use to store mutable state that must be read and modified inside Effect
transactions.
Details
Accessed values are tracked by the transaction in order to detect conflicts and in order to
track changes, a transaction will retry whenever a conflict is detected or whenever the
transaction explicitely calls to Effect.txRetry and any of the accessed TxRef values
change.
Example (Using a transactional reference)
import { Effect, TxRef } from "effect"
const program = Effect.gen(function*() {
// Create a transactional reference
const ref: TxRef.TxRef<number> = yield* TxRef.make(0)
// Use within a transaction
yield* Effect.tx(Effect.gen(function*() {
const current = yield* TxRef.get(ref)
yield* TxRef.set(ref, current + 1)
}))
const final = yield* TxRef.get(ref)
console.log(final) // 1
})
TxRef<any>,
{
readonly version: numberversion: number
value: anyvalue: any
}
>
}
>()("effect/Effect/Transaction") {}