Julia v1.5 Release Notes
========================

New language features
---------------------
* Macro calls `@foo {...}` can now also be written `@foo{...}` (without the space) ([#34498]).

Language changes
----------------

* The interactive REPL now uses "soft scope" for top-level expressions: an assignment inside a
  scope block such as a `for` loop automatically assigns to a global variable if one has been
  defined already. This matches the behavior of Julia versions 0.6 and prior, as well as
  [IJulia](https://github.com/JuliaLang/IJulia.jl).
  Note that this only affects expressions interactively typed or pasted directly into the
  default REPL ([#28789], [#33864]).

* Outside of the REPL (e.g. in a file), assigning to a variable within a top-level scope
  block is considered ambiguous if a global variable with the same name exists.
  A warning is given if that happens, to alert you that the code will work differently
  than in the REPL.
  A new command line option `--warn-scope` controls this warning ([#33864]).

* Converting arbitrary tuples to `NTuple`, e.g. `convert(NTuple, (1, ""))` now gives an error,
  where it used to be incorrectly allowed. This is because `NTuple` refers only to homogeneous
  tuples (this meaning has not changed) ([#34272]).

* In docstrings, a level-1 markdown header "Extended help" is now
  interpreted as a marker dividing "brief help" from "extended help."
  The REPL help mode only shows the brief help (the content before the
  "Extended help" header) by default; prepend the expression with '?'
  (in addition to the one that enters the help mode) to see the full
  docstring. ([#25930])

* The syntax `(;)` (which was deprecated in v1.4) now creates an empty named tuple ([#30115]).

Multi-threading changes
-----------------------


Build system changes
--------------------


New library functions
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* New functions `mergewith` and `mergewith!` supersede `merge` and `merge!` with `combine`
  argument.  They don't have the restriction for `combine` to be a `Function` and also
  provide one-argument method that returns a closure.  The old methods of `merge` and
  `merge!` are still available for backward compatibility ([#34296]).
* The new `isdisjoint` function indicates whether two collections are disjoint ([#34427]).

New library features
--------------------
* Function composition now works also on one argument `∘(f) = f` (#34251)

* `isapprox` (or `≈`) now has a one-argument "curried" method `isapprox(x)` which returns a function, like `isequal` (or `==`)` ([#32305]).
* `Ref{NTuple{N,T}}` can be passed to `Ptr{T}`/`Ref{T}` `ccall` signatures ([#34199])


Standard library changes
------------------------
* The `@timed` macro now returns a `NamedTuple` ([#34149])
* New `supertypes(T)` function returns a tuple of all supertypes of `T` ([#34419]).

#### LinearAlgebra
* The BLAS submodule now supports the level-2 BLAS subroutine `hpmv!` ([#34211]).
* `normalize` now supports multidimensional arrays ([#34239])
* `lq` factorizations can now be used to compute the minimum-norm solution to under-determined systems ([#34350]).

#### Markdown


#### Random


#### REPL


#### SparseArrays
* `lu!` accepts `UmfpackLU` as an argument to make use of its symbolic factorization.

#### Dates

#### Statistics


#### Sockets


Deprecated or removed
---------------------

External dependencies
---------------------

Tooling Improvements
---------------------


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