Julia v1.14 Release Notes
New language features
It is now possible to control which version of the Julia syntax will be used to parse a package by setting the
compat.juliaorsyntax.julia_versionkey in Project.toml. This feature is similar to the notion of "editions" in other language ecosystems and will allow non-breaking evolution of Julia syntax in future versions. See the "Syntax Versioning" section in the code loading documentation (#60018).ᵅ(U+U+1D45),ᵋ(U+1D4B),ᶲ(U+1DB2),˱(U+02F1),˲(U+02F2), andₔ(U+2094) can now also be used as operator suffixes, accessible as\^alpha,\^epsilon,\^ltphi,\_<,\_>, and\_schwaat the REPL (#60285).The
@labelmacro can now create labeled blocks that can be exited early withbreak name [value]. Use@label name exprfor named blocks or@label exprfor anonymous blocks. Anonymous@labelblocks participate in the default break scope: a plainbreakorbreak _exits the innermost breakable scope, whether it is a loop or an@labelblock. Thecontinuestatement also supports labels withcontinue nameto continue a labeled loop (#60481).typegroupblocks allow defining mutually recursive struct types that reference each other in their field types. All types in the group are resolved atomically at the end of the block (#60569).
Language changes
Compiler/Runtime improvements
Type inference now refines field types through conditional checks and call signatures. For example, after
if !isnothing(x.field), inference knowsx.fieldis notnothingwithin the branch. Similarly, after a call likefunc(x.field)wherefunc(::Int)is the only matching method, inference refinesx.fieldtoInt. This works for immutable struct fields andconstfields of mutable structs. Mutable (non-const) fields are not supported due to the lack of per-object memory effect tracking; for those, the recommended pattern remains storing the field value in a local variable before the check (e.g.val = x.field; if !isnothing(val) ... end) (#41199, #47574).
Command-line option changes
Multi-threading changes
New functions
Threads.atomic_fence_heavyandThreads.atomic_fence_lightprovide support for asymmetric atomic fences, speeding up atomic synchronization where one side of the synchronization runs significantly less often than the other (#60311).Threads.@threadsnow supports array comprehensions with syntax like@threads [f(i) for i in 1:n], filtered comprehensions like@threads [f(i) for i in 1:n if condition(i)], typed comprehensions like@threads Float64[f(i) for i in 1:n], and multi-dimensional comprehensions like@threads [f(i,j) for i in 1:n, j in 1:m](preserves dimensions). All scheduling options (:static,:dynamic,:greedy) are supported. Results preserve element order for:staticand:dynamicscheduling;:greedydoes not guarantee order. Non-indexable iterators are also supported. (#59019)
Build system changes
New library functions
Base.generating_output()has been madepublic(but not exported) to allow checking whether the current process is performing compilation for a pkgimage/sysimage (#61224).
New library features
IOContextsupports a new booleanhexunsignedoption that allows for printing unsigned integers in decimal instead of hexadecimal (#60267).
Standard library changes
codepoint(c)now succeeds for overlong encodings.Base.ismalformed,Base.isoverlong, andBase.show_invalidare nowpublicand documented (but not exported) (#55152).
JuliaSyntaxHighlighting
LinearAlgebra
Markdown
Support "raw" or "inline" HTML inside Markdown data (#60629, #60632, #60732)
Support autolinks for email addresses (#60570)
Many improvements and bugfixes for rendering Markdown lists in a terminal (#55456, #60519)
Strikethrough text via
~strike~or~~through~~is now supported by the Markdown parser. (#60537)Many, many bug fixes and minor tweaks; overall behavior is now much closer to CommonMark (#59977, #60502)
Profile
Random
REPL
Test
@test,@test_throws, and@test_brokennow support acontextkeyword argument that provides additional information displayed on test failure. This is useful for debugging which specific case failed in parameterized tests (#60501).@test_throws,@test_warn,@test_nowarn,@test_logs, and@test_deprecatednow supportbrokenandskipkeyword arguments for consistency with@test(#60543).New functions
detect_closure_boxesanddetect_closure_boxes_allfind methods that allocateCore.Boxin their lowered code, which can indicate performance issues from captured variables in closures.
Dates
unix2datetimenow accepts a keyword argumentlocaltime=trueto use the host system's local time zone instead of UTC (#50296).