20 lines
612 B
TypeScript
20 lines
612 B
TypeScript
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/**
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* Helper functions for objects.
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*/
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import { hasOwnProperty } from "../types";
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/**
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* If the given value is an object this function returns the property specified by `key` if it exists.
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*
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* @param arg - Value to treat as an object to look up the property.
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* @param key - Key indexing the property.
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* @returns The property of the given object indexed by `key` or `undefined` if `arg` is not an object
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* or has no property `key`.
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*/
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export function getFieldIfExists(
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arg: unknown,
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key: PropertyKey
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): unknown | undefined {
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return hasOwnProperty(arg, key) ? arg[key] : undefined;
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}
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