array-view-ts

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import { IndexError } from "./excpetions";
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/**
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 * Normalizes an index value within the range of a container length,
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 * optionally throwing an error if the index is out of range.
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 *
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 * @param {number} index - The index value to normalize.
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 * @param {number} containerLength - The length of the container or array.
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 * @param {boolean} [throwError=true] - Optional flag to indicate whether to throw an error if the index is out of range.
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 *
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 * @returns {number} The normalized index value within the range of the container length.
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 */
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export function normalizeIndex(index: number, containerLength: number, throwError: boolean = true): number {
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  const dist = index >= 0 ? index : Math.abs(index) - 1;
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  if (throwError && dist >= containerLength) {
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    throw new IndexError(`Index ${index} is out of range.`);
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  }
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  return index < 0 ? containerLength + index : index;
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}
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export function isCountable(target: any): boolean {
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  return target.length !== undefined;
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}
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