Dates and Time

The time domain connects calendar dates and daily clock readings with intervals, dated instants, and elapsed-time measurements. Start with the overview to choose a type for your task, then follow the topics for practical examples.

• Dates and Time Overview
  • Choosing a Type
  • Constructing Dates and Times
  • Choosing and Resolving Time Zones
  • Expressing Amounts and Intervals
  • Calendar Calculations
  • Customizing ISO Date and Time Output
  • Measuring Elapsed Time
  • Running the Topic Demos
• Working with Dates
  • A Calendar Date on Its Own
  • Constructing a Date
  • Checking and Inspecting a Date
  • Converting a Date for Display or Storage
  • Moving Through the Calendar
  • Related Clock, Interval, and Instant Types
• Working with Times
  • A Clock Reading Within One Day
  • Constructing a Time
  • Comparing Times and Accessing Clock Fields
  • Time since Midnight, Interval, and Text Conversions
  • Calculating Across Midnight
  • Choosing a Dated or Zoned Value
• Working with UTC Timestamps
  • Choosing an Instant Type
  • Constructing and Checking an Instant
  • Parsing and Formatting ISO Timestamp Text
  • Storing Fields and Portable Bytes
  • Timestamp and DateTime Conversions and Display Zones
  • Converting Epoch Counts Without Losing Meaning
  • Shifting an Instant by a Fixed Interval
  • Finding the Distance Between Instants
  • Continuing with Calendar and Clock Tasks
• Working with DateTime Values
  • Keeping an Instant and Its Display Together
  • Resolving Calendar Fields
  • Reading Local and UTC Fields
  • Comparing Instants and Comparing Complete Values
  • Changing the Display and Resolving Clock Transitions
  • Reading and Writing ISO Text
  • Choosing an Epoch and an External Number Format
  • Applying Elapsed and Calendar Changes
  • Keeping a Recurring Local Time
• Customizing ISO Date and Time Output
  • ISO 8601 Representations and Output Requirements
  • Choosing the Formatting Flags
  • Selecting the Displayed Precision
  • Related Date, Time, Timestamp, and Interval Topics
• Working with Whole-Second Durations
  • Choosing a Fixed Interval
  • Building a Duration
  • Combining Intervals and Checking a Budget
  • Splitting a Total into Components
  • Passing the Interval to Another API
  • Applying Whole-Second Intervals
• Writing Time Values with Literals
  • Bringing the Suffixes into Scope
  • Choosing a Unit and Writing a Signed Amount
  • Choosing a Representation for an Expression
  • Integer Precision and Representable Bounds
• Working with Typed Time Amounts
  • A Quantity Is Different from a Calendar Position
  • Time Units and Conversion Groups
  • Creating and Inspecting an Amount
  • Converting to a Compatible Unit
  • Calculating and Comparing in One Unit
  • Giving Calendar Quantities a Starting Date
• Working with Precise Time Intervals
  • Choosing Nanosecond Precision
  • Constructing an Interval
  • Choosing a Factory and Overflow Policy
  • Combining and Comparing Intervals
  • Handling Arithmetic Boundaries
  • Converting Totals to Another Unit
  • Presenting an Interval
  • Measuring and Applying an Interval
• Customizing Time Interval Output
  • Starting with a Preset
  • Adjusting Individual Options
  • Combining Precision Settings
  • Formatting Calendar Changes
  • Reusing a Format Across an Application
• Understanding Calendar Changes
  • Choosing a Calendar Change
  • Composing a Change
  • Combining Changes Before Application
  • Applying Components in Order
  • Calendar Changes and Local Time
  • Handling Range Boundaries
  • Converting to a Fixed Interval
• Working with Calendar and Time Parts
  • Calendar Positions versus Time Quantities
  • Available Parts and Their Numbering
  • Constructing and Checking a Part
  • Converting Calendar Labels to Zero-Based Amounts
  • Finding Lengths and Valid Days
  • Navigating Across Calendar Boundaries
  • Finding a Weekday Occurrence
  • Converting Ordinal Dates
  • DateParts, TimeParts, and DateTimeParts
• Measuring Elapsed Time
  • Choosing an Elapsed-Time Clock
  • Timing an Operation
  • Timing Successive Phases
  • Checking a Time Budget
  • Elapsed-Time Measurement Accuracy and Overhead
• Working with Monotonic Time Points
  • Choosing the Clock for Your Task
  • Recording Checkpoints
  • Calculating Elapsed Intervals
  • Representing a Deadline
  • Interoperating with Standard Library APIs
• Keeping a Wall-Clock Time with Its Zone
  • A Daily Reading Is Not Yet an Instant
  • Building and Inspecting the Value
  • Resolving a Chosen Date
  • When a Reading Repeats or Does Not Occur
  • Displaying the Intended Time
  • Keeping a Local Time Across Dates
• Working with Time Zones
  • A Zone Describes Rules; an Offset Describes a Shift
  • Choosing a Zone
  • Inspecting and Comparing Zones
  • Displaying an Existing Instant
  • Interpreting Local Input
  • Understanding Clock Transitions
  • Using the System-Local Zone
  • Keeping Identity and Offset Details Distinct
  • Understanding the Bundled Rules