idlize

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/*
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 * Copyright (c) 2022-2024 Huawei Device Co., Ltd.
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 * Licensed under the Apache License, Version 2.0 (the "License");
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 * you may not use this file except in compliance with the License.
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 * You may obtain a copy of the License at
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 *
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 * http://www.apache.org/licenses/LICENSE-2.0
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 *
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 * Unless required by applicable law or agreed to in writing, software
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 * distributed under the License is distributed on an "AS IS" BASIS,
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 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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 * See the License for the specific language governing permissions and
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 * limitations under the License.
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 */
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import { __context, __id } from "../internals"
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import { State } from "../states/State"
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/**
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 * @param name - a name of a context state
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 * @returns the named context state or `undefined` if it does not exist
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 * @memo:intrinsic
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 */
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export function contextLocal<Value>(name: string): State<Value> | undefined {
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    return __context().stateBy<Value>(name, undefined)
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}
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/**
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 * @param name - a name of a context state
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 * @returns a value of a context state
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 * @throws Error if a named context state does not exist
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 * @memo:intrinsic
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 */
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export function contextLocalValue<Value>(name: string): Value {
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    return __context().valueBy<Value>(name, undefined)
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}
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/**
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 * Creates a named state with the specified value in the context scope.
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 * The specified value will be propagated immediately during recomposition.
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 * Note that the state name must not be dynamically changed.
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 *
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 * @param name - a name of a context state
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 * @param value - a value of a named state to share within the given content
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 * @param content - a scope content in which a named state is available
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 * @memo:intrinsic
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 */
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export function contextLocalScope<Value>(
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    name: string,
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    value: Value,
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    /** @memo */
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    content: () => void
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) {
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    const scope = __context().scope<void>(__id(), 1, undefined, undefined, undefined, undefined)
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    scope.param(0, value, undefined, name, true) // can be found by name
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    return scope.unchanged ? scope.cached : scope.recache(content())
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}
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