source/teaql-ts/examples/browser-sqlite/assist/expression-customer_order.md

TypeScript Assist — Expression Customer Order

The generated E facade preserves Value, loaded null/undefined, and NotLoaded. eval() returns a native value for the first two and throws TeaQLNotLoadedError for the third. orElse is nullish-only and never hides NotLoaded.

import { E } from './E';
import { CustomerOrder } from './models/CustomerOrder';

export function extractId(entity: CustomerOrder) {
    return E.customerOrder(entity).id().eval();
}

export function extractIdOrElse(
    entity: CustomerOrder, fallback: NonNullable<CustomerOrder['id']>,
) {
    return E.customerOrder(entity).id().orElse(fallback);
}

export function extractOrderNumber(entity: CustomerOrder) {
    return E.customerOrder(entity).orderNumber().eval();
}

export function extractOrderNumberOrElse(
    entity: CustomerOrder, fallback: NonNullable<CustomerOrder['orderNumber']>,
) {
    return E.customerOrder(entity).orderNumber().orElse(fallback);
}

export function extractOrderDate(entity: CustomerOrder) {
    return E.customerOrder(entity).orderDate().eval();
}

export function extractOrderDateOrElse(
    entity: CustomerOrder, fallback: NonNullable<CustomerOrder['orderDate']>,
) {
    return E.customerOrder(entity).orderDate().orElse(fallback);
}

export function extractTotalAmount(entity: CustomerOrder) {
    return E.customerOrder(entity).totalAmount().eval();
}

export function extractTotalAmountOrElse(
    entity: CustomerOrder, fallback: NonNullable<CustomerOrder['totalAmount']>,
) {
    return E.customerOrder(entity).totalAmount().orElse(fallback);
}

export function extractVersion(entity: CustomerOrder) {
    return E.customerOrder(entity).version().eval();
}

export function extractVersionOrElse(
    entity: CustomerOrder, fallback: NonNullable<CustomerOrder['version']>,
) {
    return E.customerOrder(entity).version().orElse(fallback);
}

export function extractCustomerId(entity: CustomerOrder) {
    return E.customerOrder(entity).customerId().eval();
}

export function traverseCustomer(entity: CustomerOrder) {
    return E.customerOrder(entity).customer().eval();
}

export function extractStatusId(entity: CustomerOrder) {
    return E.customerOrder(entity).statusId().eval();
}

export function traverseStatus(entity: CustomerOrder) {
    return E.customerOrder(entity).status().eval();
}

export function aggregateOrderItemListSize(entity: CustomerOrder) {
    return E.customerOrder(entity).orderItemList().size().eval();
}

export function firstOrderItemListId(entity: CustomerOrder) {
    return E.customerOrder(entity).orderItemList().first().id().eval();
}

export function getOrderItemListId(entity: CustomerOrder, index: number) {
    return E.customerOrder(entity).orderItemList().get(index).id().eval();
}

Select every traversed field and relation. Never catch TeaQLNotLoadedError merely to supply a default, and never replace generated E accessors with optional chaining.

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TeaQL seven-language assist contract

Apply the verified Rust semantic ceiling while using only the exact TYPESCRIPT generated and runtime APIs. Discover APIs through the generated application AGENTS.md and progressive model-aware Assist. Do not inspect generated domain-library source.

• Do not create plurals by appending s or es; use the centralized generated plural.
• Human and non-human entities use different generated predicate vocabularies. Preserve forms such as “who are active” and “whose email is”; never infer them from English.
• Configure filters, projection, paging, and other query options before purpose(...). Comment may appear anywhere in the chain. Purpose enters the executable stage; execution requires both values, but comment does not have to immediately precede purpose.
• Every execute/list/stream and every save accepts exactly one context argument: UserContext. Name that argument context, never runtime; data services and global policy are injected when the context is built. Reserve runtime for process-level runtime ownership, provider/pool setup, and module assembly.
• Tenant, merchant, identity, permissions, request policy, purpose policy, hard limit, and continuous-page cursor policy come only from trusted context, never dynamic JSON or TFP.
• If the required operation is absent after current entity/action and required field Assist, stop that path and report MISSING_ASSIST. Do not guess an API or search the generated library as a fallback.
• Create each application-owned source file once. After its first compile attempt, repair only the smallest block identified by the exact compiler or test diagnostic. Preserve unrelated code; do not rewrite the complete file as an error-recovery loop.
• Before a repair that would replace more than 25% of an existing application file, stop and report LARGE_REWRITE_REQUEST with the file, exact diagnostic, reason, and estimated scope. Initial creation and model-driven regeneration are not repairs.

Capability: expression.

• Distinguish a loaded null from a field or relation that was not projected. A NotLoaded/coding error must remain visible; do not turn it into an ordinary null.
• Select every traversed relation first and use the generated E/expression API for scalar, object, and list traversal. Do not translate Java accessor names by guess.