LambdaFun.Time 1.2.1

LambdaFun.Time

High-precision time utilities for F#. A drop-in, ergonomic type for timestamping, measuring durations, sequencing time points, and doing precise arithmetic with wall-clock time. Built on top of .NET’s Stopwatch and DateTime to map high-resolution local ticks into UTC ticks, giving you high-precision “now” with familiar DateTime semantics.

• Target frameworks: .NET Framework 4.8.1, .NET Standard 2.0, .NET Core 3.1, .NET 8, .NET 9
• Language: F#, compatible with C# clients.

Why use Time?

• High-precision Now: Combines Stopwatch.GetTimestamp() with UTC ticks for precise current time.
• Safe arithmetic: Add/subtract TimeSpan or milliseconds directly on Time.
• Natural comparisons: =, <>, <, <=, >, >= work as expected.
• Interop friendly: Convert to DateTime, TimeSpan, and raw ticks easily.
• Sequences: Generate forward/backward time series, including infinite streams.

Install

• NuGet Package Manager:

  • PM> Install-Package LambdaFun.Time

• Paket CLI:

  • > dotnet paket add LambdaFun.Time --project _my_project_

Quick start

// F#
open System
open LambdaFun

let t0 = Time.Now
do something()
let t1 = Time.Now

let elapsed: TimeSpan = t1 - t0
printfn "Elapsed: %A ms" elapsed.TotalMilliseconds

// Arithmetic
let in500ms = t0 + 500
let in2_5ms = t0 + 2.5m
let in1s = t0 + TimeSpan.FromSeconds 1

// Comparison
if Time.Now >= in1s then printfn "At or past 1 second mark."

// Interop
let dt: DateTime = t0.DateTime
let ticks: int64 = t0.Ticks

API overview

• Construction

  • Time.Now: high-precision current time
  • Time(year, month, day)
  • Time(year, month, day, hour, minute, second)
  • Time(dateTime: DateTime)
  • Time.Default: zero-based sentinel time

• Properties

  • Ticks: int64
  • DateTime: DateTime
  • Age: TimeSpan (since creation, using high-precision Now)
  • Year | Month | Day | Hour | Minute | Second

• Operators

  • time + TimeSpan -> Time
  • time + int (milliseconds) -> Time
  • time + decimal (milliseconds) -> Time
  • time - TimeSpan -> Time
  • time1 - time2 -> TimeSpan
  • =, <>, <, <=, >, >=

• Sequences

  • Time.InfiniteSequence start step: seq
  • Time.Sequence start finish step: seq(forward or backward)

Usage patterns

• High-precision elapsed timing

  • Capture let t = Time.Now before work, subtract later for TimeSpan.

• Scheduling/checkpoints

  • Compute future instants with Time + TimeSpan and compare.

• Time series generation

  • Build sampling points using Time.Sequence start finish (TimeSpan.FromMilliseconds 10.0).

• Sentinel/default values

  • Use Time.Default when an optional timestamp isn’t set.

Notes

• Timezone: Time.Now maps to UTC ticks; Time.DateTime is UTC unless you convert.
• Determinism: Precision relies on Stopwatch.Frequency and monotonic ticks at runtime.
• Collections: Implements equality, hash code, and IComparable for maps/sets.

License

LGPL. See the project license for details.