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* Numeric types
* Copyright (C) 2010-2019 R-T Specialty, LLC.
* This file is part of the Liza Data Collection Framework.
* liza is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
* TypeScript's type system does not support algebraic numeric domains. A
* compromise is to provide nominal types that allow developers to assume
* that some constraint has been met, and then ensure that the type is only
* ever asserted when that constraint is explicitly validated at
* runtime. This allows us to have compile-time checks on numeric values
* under the assumption that the runtime will enforce them.
* For this to work, _it is important to always use type predicates_;
* if you explicit cast to one of these numeric types, it circumvents the
* safety provided by the system and may introduce nasty bugs, since users
* of these types assume the provided data has already been validated.
* Any number ≥ 0
* This is useful for array indexing.
export type PositiveInteger = NominalType<number, 'PositiveInteger'>;
/** Whether the given number is suitable as a PositiveInteger */
export const isPositiveInteger = ( n: number ): n is PositiveInteger => n >= 0;