dhall-1.29.0

• Supports version 13.0.0 of the standard
• BREAKING CHANGE: Generate Haskell datatype declarations from Dhall types
  • You can now use the makeHaskellTypeFromUnion Template Haskell utility
    to generate a Haskell datatype declaration from a Dhall union type
  • This helps ensure that your Haskell types and Dhall types stay in sync,
    when you want the Dhall type to be the source of truth
  • This is a breaking change because the default InterpretOptions changed
    the default handling of singleton constructors from Wrapped to Smart
  • You can preserve the old behavior using:
    autoWith defaultInterpretOptions{ singletonConstructors = Wrapped }
• BUG FIX: Fix dhall freeze --cache and dhall lint to preserve let-related comments
  • Now they match the behavior of dhall format with regard to preserving
    these comments
• BUG FIX: Fix escaping of significant leading whitespace when formatting code
  • The formatter would sometimes unnecessarily escape significant leading
    whitespace for the final line of multiline string literals, which this
    change fixes
• BUG FIX: Fix dhall encode --json for Double values
• NEW FEATURE: dhall to-directory-tree command
  • You can now generate a directory tree from a Dhall expression
  • Specifically:
    • records are converted to directories
    • Text fields are converted to files named after the field
    • Optional values are omitted if None
    • Everything else is rejected
• NEW FEATURE: Hexadecimal literals
  • See the changelog for standard version 13.0.0 for more details
• NEW FEATURE: merge works on Optional values
  • See the changelog for standard version 13.0.0 for more details
• Improve formatter
  • dhall format will now render expressions nested inside record fields or
    alternatives more compactly, including:
    • Records
    • Record completion expressions
    • Expressions wrapped in Some
    • Lists
• Exclude the using ... suffix from imports listed by dhall resolve
  • Specifically when using the --{immediate,transitive}-dependencies flags