dhall-1.15.1

• Fix infinite loop when formatting expressions containing ?
  • See: #491

dhall-1.15.0

• BREAKING CHANGE TO THE API: Support alternative imports using new ? operator
  • This adds a new constructor which affects exhaustive pattern matches
  • See: #473
• BREAKING CHANGE TO THE API: Add Integer/toDouble built-in function
  • This adds a new constructor which affects exhaustive pattern matches
  • See: #434
• BREAKING CHANGE TO THE API: Use strict Text instead of lazy Text
  • See: #455
• BREAKING CHANGE TO THE API: Remove Buildable in favor of Pretty
  • See: #459
• BREAKING CHANGE TO THE API: Removed the Parent constructor from FilePrefix
  • Instead, use Here with a ".." prefix.
  • See: #407
• BUG FIX: Disallow duplicate fields in records
  • See: #430
• BUG FIX: Fix stripping of leading whitespace in multi-line strings
  • See: #469
• BUG FIX: Fix formatting field access of an import
  • See: #471
• Add dhall freeze command
  • See: #486
• Add dhall diff command
  • See: #442
• Add dhall lint command
  • See: #484
• Change dhall-repl/dhall-hash/dhall-format to dhall subcommands
  • i.e. dhall repl/dhall hash/dhall format
  • See: #435
  • See: #452
• Add with-http cabal flag to disable support for remote imports
  • See: #482
• Added inputFrom and inputFromWith
  • These allow naming the file that the expression is coming from for better
    error messages
  • See: #464
• Performance improvements
  • See: #420
• Tutorial recommends GitHub for Prelude instead of IPFS
  • See: #479
• Pretty-print expressions in type errors
  • See: #429
• Formatting improvements
  • See: #398
  • See: #458
• Diff improvements
  • See: #455
  • See: #470
  • See: #478

dhall-1.14.0

• BREAKING CHANGE TO THE LANGUAGE: Switch grammar of Natural and Integer
  • Natural number literals are now unsigned and Integer literals always
    require a sign
  • This is a VERY disruptive change to most Dhall code in the wild but
    was unanimously agreed upon here:
    dhall-lang/dhall-lang#138
  • See also: #381
• BREAKING CHANGE TO THE LANGUAGE: Drop support for importing directories
  • Importing dir/ used to resolve to dir/@, which is no longer supported
  • See: #384
• BREAKING CHANGE TO THE LANGUAGE: Change to the grammar for imports
  • File path components can no longer contain # or ? characters
  • URL imports must now contain at least one path component
  • URL path components must match the grammar for file path components
  • See: #390
• BREAKING CHANGE TO THE API: Rename Path{,Mode,Hashed,Type} to
  Import{,Mode,Hashed,Type}
  • In practice this change is not breaking for the most common use cases
    since this also provides a Path type synonym for backwards compatibility
  • See: #376
• BUG FIX: Fix α-equivalence bug when type-checking merge
  • merge expressions would sometimes reject valid code due to a
    type-checking bug
  • See: #394
• Improve import caching
  • See: #388
  • See: #392
• Increase upper bound on tasty
  • See: #382
• Fix lower bound on insert-ordered-containers
  • See: #377

dhall-1.13.1

• Increase upper bound on ansi-terminal and megaparsec

dhall-1.13.0

• BUG FIX: Fix semantic integrity hashing support
  • Both parsing and pretty-printing semantic hashes were broken since version
    1.11.0
  • See: #345
• BUG FIX: Allow leading whitespace in interpolated expresssions
  • See: #369
• BUG FIX: Fix deriving (Interpret) for sum types
  • The types of alternatives were not correctly included in the corresponding
    Dhall type
  • See: #348
• BREAKING CHANGE TO LANGUAGE: Records cannot store both types and terms
  • Records can also not store type-level functions (like List)
    • Records might be allowed to store type-level functions again in the
      future
  • This fixes a potential soundness bug
  • The primarily practical consequence of this change is that if you are
    hosting a "package" then you will need to split terms and types from your
    package into different records for your users to import
  • This also implies removing the ./Monoid type-level function from the
    ./Prelude/package.dhall record
  • See: #335
• BREAKING CHANGE TO THE API: Replace trifecta with megaparsec
  • This change the API to use the Parser type from megaparsec
  • This also slightly changes the type of exprFromText
  • If you program using the type classes provided by the parsers library
    then this is not a breaking change as that interface is preserved
  • See: #268
• BREAKING CHANGE TO THE API: New ⩓ operator for merging record types
  • Example: { foo : Text } ⩓ { bar : Bool } = { foo : Text, bar : Bool }
  • This is breaking because it adds a new constructor to the Expr type
  • See: #342
• BREAKING CHANGE TO THE API: New support for projecting a subset of fields
  • Example: { x = 1, y = 2, z = 3 }.{ x, y } = { x = 1, y = 2 }
  • This is breaking because it adds a new constructor to the Expr type
  • See: #350
• API+UX feature: New support for pretty-printing diffs of Dhall expressions
  • Error messages also use this feature to simplify large type mismatches
  • There is also a new Dhall.Diff module
  • See: #336
• Add version, resolve, type, and normalize sub-commands to interpreter
  • See: #352
• Support GHC 7.10.3
  • See: #340
• :type command in dhall-repl now only displays the type
  • Before it would also display the original expression
  • See: #344
• Trim dependency tree
  • See: #351
  • See: #268
  • See: #355

dhall-1.12.0

• Additional changes to support GHC 8.4
  • See: #331
• BREAKING CHANGE TO API: Replace dependency on text-format with formatting
  • This replace the Data.Text.Buildable.Buildable instances with
    Formatting.Buildable.Buildable instances, which is why this is a
    breaking change
  • text-format is no longer maintained and blocking GHC 8.4 support
  • See: #330

dhall-1.11.1

• Support GHC 8.4
  • See: #321
• Fix α-normalization bug
  • Note that this is not a type-checking bug. This only affects users who
    were directly using the alphaNormalize function from the Haskell API
    because let expressions were not correctly α-normalized
  • See: #319
• Slight tweak to syntax highlighting
  • See: #324
• Increase upper bound on ansi-terminal and exceptions
  • See: #322
  • See: #325

dhall-1.11.0

• BREAKING CHANGE TO THE API: Fix {Natural,Optional,List}/build semantics to
  match standard
  • This is a breaking change because the OptionalLit and ListLit
    constructors changed their representations to efficiently support the
    standard semantics
  • ListLit now stores a Data.Sequence.Seq instead of a
    Data.Vector.Vector
  • OptionalLit now stores a Maybe instead of a Data.Vector.Vector
  • See: #300
• BREAKING CHANGE TO THE COMMAND LINE: dhall executable always formats output
  • Previously you had to opt into formatting using --pretty
  • Now formatting is obligatory and the --pretty flag is gone
  • See: #303
• Feature: New :save command for dhall-repl
  • Now you can save an expression to a file: ./yourFile = someExpression
  • See: #309
• Improvement: Add new simplifications to match standard
  • See: #312
  • See: #316
• Improvement: Fix equivalence check to match standard
  • Practically this means that more corner cases of the language correctly
    type-check than before
• Improvement: New --plain flag to disable syntax highlighting
  • See: #310
• Improvement: Prelude now provides an umbrella package.dhall import
  • This is primarily for convenience
  • See: #298
• Improvement: Context is now normalized
  • See: #302
• Replace cryptohash dependency with cryptonite
  • See: 5d20129
• Increase upper bound on exceptions
  • See: #306
• Fix type error in tutorial
  • See: 5a9126b

dhall-1.10.0

• Feature: Records/unions can now have fields/alternatives that are types
  • i.e. { foo = Text, bar = List } is legal now
  • See: #273
• Feature: New dhall-repl for interactively evaluating Dhall expressions
  • See: #266
• Feature: Syntax highlighting
  • See: #260
• Feature: BREAKING CHANGE TO THE API: dhall-format preserves field order
  • This changes the syntax tree to use an InsOrdHashMap instead of a Map
• BREAKING CHANGE TO THE API: Use Haskell's Scientific type
  • This is fixes the interpreter to correct handle really large/small numbers
  • This also allows marshaling into Haskell's Scientific type
  • See: #256
• BREAKING CHANGE TO THE API: Remove system-filepath/system-fileio dependencies
  • Now the library uses Prelude.FilePath
  • See: #248
• Feature: Labels can now begin with reserved names
  • i.e. List/map is now a legal label
  • See: #255
• Fix: Rendered labels are now correctly escaped if they are numbers
  • See: #252
• Add the instance Interpret String.
  • See: #247
• Fix: Custom contexts passed to typeWith are now checked
  • This prevents a custom context from triggering an infinite loop
  • See: #259

dhall-1.9.1

• dhall-format now emits single-quoted strings for multi-line strings
  • See: #237
• Improved error messages for list elements with the wrong type
  • See: #236
• Change lens dependency to lens-family-core
  • See: #238