uint.ts

/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/

export const enum Constants {
	/**
	 * MAX SMI (SMall Integer) as defined in v8.
	 * one bit is lost for boxing/unboxing flag.
	 * one bit is lost for sign flag.
	 * See https://thibaultlaurens.github.io/javascript/2013/04/29/how-the-v8-engine-works/#tagged-values
	 */
	MAX_SAFE_SMALL_INTEGER = 1 << 30,

	/**
	 * MIN SMI (SMall Integer) as defined in v8.
	 * one bit is lost for boxing/unboxing flag.
	 * one bit is lost for sign flag.
	 * See https://thibaultlaurens.github.io/javascript/2013/04/29/how-the-v8-engine-works/#tagged-values
	 */
	MIN_SAFE_SMALL_INTEGER = -(1 << 30),

	/**
	 * Max unsigned integer that fits on 8 bits.
	 */
	MAX_UINT_8 = 255, // 2^8 - 1

	/**
	 * Max unsigned integer that fits on 16 bits.
	 */
	MAX_UINT_16 = 65535, // 2^16 - 1

	/**
	 * Max unsigned integer that fits on 32 bits.
	 */
	MAX_UINT_32 = 4294967295, // 2^32 - 1

	UNICODE_SUPPLEMENTARY_PLANE_BEGIN = 0x010000
}

export function toUint8(v: number): number {
	if (v < 0) {
		return 0;
	}
	if (v > Constants.MAX_UINT_8) {
		return Constants.MAX_UINT_8;
	}
	return v | 0;
}

export function toUint32(v: number): number {
	if (v < 0) {
		return 0;
	}
	if (v > Constants.MAX_UINT_32) {
		return Constants.MAX_UINT_32;
	}
	return v | 0;
}