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A bit of shuffling in the CHANGEGLOG

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Edwin Brady 2020-05-22 14:21:48 +01:00
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CHANGELOG.md
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@ -5,21 +5,12 @@ The implementation is now self-hosted. To initialise the build, either use
the [bootstrapping version of Idris2](https://github.com/edwinb/Idris2-boot)
or build from the generated Scheme, using `make bootstrap`.
Compiler updates:
* Data types with a single constructor, with a single unerased arguments,
are translated to just that argument, to save repeated packing and unpacking.
(c.f. `newtype` in Haskell)
+ A data type can opt out of this behaviour by specifying `noNewtype` in its
options list. `noNewtype` allows code generators to apply special handling
to the generated constructor/deconstructor, for a newtype-like data type,
that would otherwise be optimised away.
* 0-multiplicity constructor arguments are now properly erased, not just
given a placeholder null value.
Language changes:
* `total`, `covering` and `partial` flags on functions now have an effect.
* Fields of records can be accessed (and updated) using the dot syntax,
such as `r.field1.field2` or `record { field1.field2 = 42 }`.
For details, see https://idris2.readthedocs.io/en/latest/reference/records.html
* %transform directive, for declaring transformation rules on runtime
expressions. Transformation rules are automatically added for top level
implementations of interfaces.
@ -34,22 +25,27 @@ Library additions:
* New modules in `contrib` for JSON (`Language.JSON.*`); random numbers
(`System.Random`)
Compiler updates:
* Data types with a single constructor, with a single unerased arguments,
are translated to just that argument, to save repeated packing and unpacking.
(c.f. `newtype` in Haskell)
+ A data type can opt out of this behaviour by specifying `noNewtype` in its
options list. `noNewtype` allows code generators to apply special handling
to the generated constructor/deconstructor, for a newtype-like data type,
that would otherwise be optimised away.
* 0-multiplicity constructor arguments are now properly erased, not just
given a placeholder null value.
Other improvements:
* Various performance improvements in the typechecker:
+ Noting which metavariables are blocking unification constraints, so that
they only get retried if those metavariables make progress.
+ Evaluating `fromInteger` at compile time.
+ In the run-time, reuse the old heap after garbage collection if it
hasn't been resized, to avoid unnecessary system calls.
* Extend Idris2's literate mode to support reading Markdown and OrgMode files.
For more details see: https://idris2.readthedocs.io/en/latest/reference/literate.html
* Fields of records can be accessed (and updated) using the dot syntax,
such as `r.field1.field2` or `record { field1.field2 = 42 }`.
For details, see https://idris2.readthedocs.io/en/latest/reference/records.html
Changes since Idris 1
---------------------