Plutus.V1.Ledger.Time

• 1. 📜 Overview

• 2. 🔧 LANGUAGE PRAGMAS AND IMPORTS

• 3. 🗄️ Data Types

  • 3.1 ⏱️ DiffMilliSeconds

  • 3.2 ⏲️ POSIXTime

  • 3.3 📅 POSIXTimeRange

• 4. ⚙️ Functions

  • 4.1 ↔️ fromMilliSeconds

• 5. 🤝 Typeclass Instances

• 6. 🏭 On-Chain Derivations

• 7. 📚 Glossary

---

1 📜 Overview

The Plutus.V1.Ledger.Time module defines types and functions for working with time in Plutus on-chain code:

• DiffMilliSeconds: duration measured in milliseconds.

• POSIXTime: absolute time since the Unix epoch, in milliseconds.

• POSIXTimeRange: alias for Interval POSIXTime, representing valid time windows.

• Utility to convert between DiffMilliSeconds and POSIXTime.

All types derive numeric, ordering, and on-chain serialization classes for use in scripts.

---

2 🔧 LANGUAGE PRAGMAS AND IMPORTS

{-# LANGUAGE DeriveAnyClass       #-}
{-# LANGUAGE DeriveGeneric        #-}
{-# LANGUAGE DerivingStrategies   #-}
{-# LANGUAGE FlexibleContexts     #-}
{-# LANGUAGE FlexibleInstances    #-}
{-# LANGUAGE MonoLocalBinds       #-}
{-# LANGUAGE NoImplicitPrelude    #-}
{-# LANGUAGE OverloadedStrings    #-}
{-# LANGUAGE TemplateHaskell      #-}
{-# LANGUAGE UndecidableInstances #-}
{-# OPTIONS_GHC -Wno-identities #-}
{-# OPTIONS_GHC -fno-ignore-interface-pragmas #-}
{-# OPTIONS_GHC -fno-omit-interface-pragmas #-}

module Plutus.V1.Ledger.Time (
    DiffMilliSeconds(..),
    POSIXTime(..),
    POSIXTimeRange,
    fromMilliSeconds
  ) where

import Control.DeepSeq (NFData)
import GHC.Generics    (Generic)
import Plutus.V1.Ledger.Interval (Interval)
import PlutusTx qualified
import PlutusTx.Lift (makeLift)
import PlutusTx.Prelude
import Prelude qualified as Haskell
import Prettyprinter (Pretty(pretty), (<+>))

• Deriving: generic, anyclass, numeric, and on-chain ToData/FromData.

• Imports: Interval for time ranges, PlutusTx.Prelude for on-chain code.

---

3 🗄️ Data Types

3.1 ⏱️ DiffMilliSeconds

newtype DiffMilliSeconds = DiffMilliSeconds Integer
  deriving stock   (Haskell.Eq, Haskell.Ord, Haskell.Show, Generic)
  deriving anyclass (NFData)
  deriving newtype (
    Haskell.Num,
    AdditiveSemigroup,
    AdditiveMonoid,
    AdditiveGroup,
    Haskell.Enum,
    Eq,
    Ord,
    Haskell.Real,
    Haskell.Integral,
    PlutusTx.ToData,
    PlutusTx.FromData,
    PlutusTx.UnsafeFromData
  )

• Represents a duration in milliseconds.

• Derives all standard numeric and on-chain data classes via newtype.

3.2 ⏲️ POSIXTime

newtype POSIXTime = POSIXTime { getPOSIXTime :: Integer }
  deriving stock   (Haskell.Eq, Haskell.Ord, Haskell.Show, Generic)
  deriving anyclass (NFData)
  deriving newtype (
    AdditiveSemigroup,
    AdditiveMonoid,
    AdditiveGroup,
    Eq,
    Ord,
    Enum,
    PlutusTx.ToData,
    PlutusTx.FromData,
    PlutusTx.UnsafeFromData,
    Haskell.Num,
    Haskell.Enum,
    Haskell.Real,
    Haskell.Integral
  )

• Represents milliseconds since 1970-01-01T00:00:00Z.

• Convenient numeric operations and on-chain serialization.

instance Pretty POSIXTime where
  pretty (POSIXTime i) = "POSIXTime" <+> pretty i

• Pretty instance for human-readable output.

3.3 📅 POSIXTimeRange

type POSIXTimeRange = Interval POSIXTime

• Alias for time intervals, e.g., validity windows on transactions.

---

4 ⚙️ Functions

4.1 ↔️ fromMilliSeconds

{-# INLINABLE fromMilliSeconds #-}
fromMilliSeconds :: DiffMilliSeconds -> POSIXTime
fromMilliSeconds (DiffMilliSeconds s) = POSIXTime s

• Converts a DiffMilliSeconds duration into a POSIXTime offset.

• Use case: add or subtract durations to/from POSIXTime values in contracts.

---

5 🤝 Typeclass Instances

• Eq, Ord, Show, Generic, NFData for both DiffMilliSeconds and POSIXTime.

• Numeric (Num, Integral, etc.) and Additive for arithmetic.

• On-chain serialization via PlutusTx.ToData, FromData, and UnsafeFromData.

---

6 🏭 On-Chain Derivations

makeLift ''DiffMilliSeconds
makeLift ''POSIXTime

• makeLift Template Haskell to embed these types in PlutusTx code.

---

7 📚 Glossary

• DiffMilliSeconds: a wrapper around Integer representing milliseconds.

• POSIXTime: milliseconds since UNIX epoch.

• POSIXTimeRange: interval of POSIXTime, used for validity ranges.

• Interval: generic open/closed interval type from Plutus.V1.Ledger.Interval.

• MonoLocalBinds and UndecidableInstances: GHC pragmas enabling certain instance definitions.

• makeLift: TH function to create on-chain Lift instances.

• AdditiveSemigroup / Monoid / Group: algebraic classes for addition.

• INLINABLE: pragma exposing function for on-chain optimization.