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@polkadot/util

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"use strict"; Object.defineProperty(exports, "__esModule", { value: true }); exports.u8aToHex = u8aToHex; var _alphabet = require("../hex/alphabet"); // Copyright 2017-2022 @polkadot/util authors & contributors // SPDX-License-Identifier: Apache-2.0 /** @internal */ function hex(value) { const mod = value.length % 2; const length = value.length - mod; const dv = new DataView(value.buffer, value.byteOffset); let result = ''; for (let i = 0; i < length; i += 2) { result += _alphabet.U16_TO_HEX[dv.getUint16(i)]; } if (mod) { result += _alphabet.U8_TO_HEX[dv.getUint8(length)]; } return result; } /** * @name u8aToHex * @summary Creates a hex string from a Uint8Array object. * @description * `UInt8Array` input values return the actual hex string. `null` or `undefined` values returns an `0x` string. * @example * <BR> * * ```javascript * import { u8aToHex } from '@polkadot/util'; * * u8aToHex(new Uint8Array([0x68, 0x65, 0x6c, 0x6c, 0xf])); // 0x68656c0f * ``` */ function u8aToHex(value) { let bitLength = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : -1; let isPrefixed = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : true; const length = Math.ceil(bitLength / 8); return `${isPrefixed ? '0x' : ''}${!value || !value.length ? '' : length > 0 && value.length > length ? `${hex(value.subarray(0, length / 2))}${hex(value.subarray(value.length - length / 2))}` : hex(value)}`; }