[API Proposal]: Expose the remaining const values in TimeSpan

[IDisposable]

Background and motivation

In the TimeSpan class there are a few public const values that are generally applicable that are usefully exposed.

There are also a bunch more that are internal const but would be generally useful for other code and are not more implementation driven than the already exposed const values.

These values should be exposed publicly on the TimeSpan class.

Note: NOT suggesting we expose the truly internal const values that are related to MinTicks and MaxTicks. They could be included but are just not as naturally useful elsewhere.

API Proposal

namespace System.Collections.Generic;

public class TimeSpan: // elided details
{
        // more elision

        public const long MicrosecondsPerMillisecond = TicksPerMillisecond / TicksPerMicrosecond; //           1,000
        public const long MicrosecondsPerSecond = TicksPerSecond / TicksPerMicrosecond;           //       1,000,000
        public const long MicrosecondsPerMinute = TicksPerMinute / TicksPerMicrosecond;           //      60,000,000
        public const long MicrosecondsPerHour = TicksPerHour / TicksPerMicrosecond;               //   3,600,000,000
        public const long MicrosecondsPerDay = TicksPerDay / TicksPerMicrosecond;                 //  86,400,000,000

        public const long MillisecondsPerSecond = TicksPerSecond / TicksPerMillisecond;           //           1,000
        public const long MillisecondsPerMinute = TicksPerMinute / TicksPerMillisecond;           //          60,000
        public const long MillisecondsPerHour = TicksPerHour / TicksPerMillisecond;               //       3,600,000
        public const long MillisecondsPerDay = TicksPerDay / TicksPerMillisecond;                 //      86,400,000

        public const long SecondsPerMinute = TicksPerMinute / TicksPerSecond;                     //              60
        public const long SecondsPerHour = TicksPerHour / TicksPerSecond;                         //           3,600
        public const long SecondsPerDay = TicksPerDay / TicksPerSecond;                           //          86,400

        public const long MinutesPerHour = TicksPerHour / TicksPerMinute;                         //              60
        public const long MinutesPerDay = TicksPerDay / TicksPerMinute;                           //           1,440

        public const long HoursPerDay = TicksPerDay / TicksPerHour;                               //              24
}

API Usage

if (TimeSpan.MinutesPerHour * numHours) > TimeSpan.MinutesPerDay * 7)
    Console.WriteLine("That's really weeks");

Alternative Designs

N/A

Risks

Since these are compile-time constant values, there would be no runtime cost in either memory or execution overhead. Additionally they would centralize basic real-world facts to one logical location (TimeSpan).

[ghost]

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Issue Details

---

Background and motivation

In the TimeSpan class there are a few public const values that are generally applicable that are usefully exposed.

There are also a bunch more that are internal const but would be generally useful for other code and are not more implementation driven than the already exposed const values.

These values should be exposed publicly on the TimeSpan class.

Note: NOT suggesting we expose the truly internal const values that are related to MinTicks and MaxTicks. They could be included but are just not as naturally useful elsewhere.

API Proposal

namespace System.Collections.Generic;

public class TimeSpan: // elided details
{
        // more elision

        public const long MicrosecondsPerMillisecond = TicksPerMillisecond / TicksPerMicrosecond; //           1,000
        public const long MicrosecondsPerSecond = TicksPerSecond / TicksPerMicrosecond;           //       1,000,000
        public const long MicrosecondsPerMinute = TicksPerMinute / TicksPerMicrosecond;           //      60,000,000
        public const long MicrosecondsPerHour = TicksPerHour / TicksPerMicrosecond;               //   3,600,000,000
        public const long MicrosecondsPerDay = TicksPerDay / TicksPerMicrosecond;                 //  86,400,000,000

        public const long MillisecondsPerSecond = TicksPerSecond / TicksPerMillisecond;           //           1,000
        public const long MillisecondsPerMinute = TicksPerMinute / TicksPerMillisecond;           //          60,000
        public const long MillisecondsPerHour = TicksPerHour / TicksPerMillisecond;               //       3,600,000
        public const long MillisecondsPerDay = TicksPerDay / TicksPerMillisecond;                 //      86,400,000

        public const long SecondsPerMinute = TicksPerMinute / TicksPerSecond;                     //              60
        public const long SecondsPerHour = TicksPerHour / TicksPerSecond;                         //           3,600
        public const long SecondsPerDay = TicksPerDay / TicksPerSecond;                           //          86,400

        public const long MinutesPerHour = TicksPerHour / TicksPerMinute;                         //              60
        public const long MinutesPerDay = TicksPerDay / TicksPerMinute;                           //           1,440

        public const long HoursPerDay = TicksPerDay / TicksPerHour;                               //              24
}

API Usage

if (TimeSpan.MinutesPerHour * numHours) > TimeSpan.MinutesPerDay * 7)
    Console.WriteLine("That's really weeks");

Alternative Designs

N/A

Risks

Since these are compile-time constant values, there would be no runtime cost in either memory or execution overhead. Additionally they would centralize basic real-world facts to one logical location (TimeSpan).

Author:	IDisposable
Assignees:	-
Labels:	api-suggestion, untriaged, area-System.DateTime
Milestone:	-

[IDisposable]

Is this something we can add to the API review?

[tannergooding]

CC. @tarekgh, this is a relatively simple ask and I know I've had to redefine such constants myself in personal projects to help with various extension methods or other time related structs used (such as a Timestamp struct used to track frame timings in a game engine).

[tarekgh]

I am fine to proceed with the proposal. I don't have any feedback as the proposal looks good to me as it is. I'll mark this as ready for review.

[IDisposable]

Should I reopen the PR or start a new one? :)

[tarekgh]

@IDisposable please wait till the issue gets reviewed by the design committee and then we can reopen the PR. Thanks!