vlang/v 0.3.5

on GitHub

Improvements in the language

• Coroutines with a scheduler. Only Linux/macOS for now, requires -use-coroutines and
  coroutines.sleep() instead of time.sleep(). They work with IO and net, but not with GC
  for now.
• spawn now spawns system threads, go spawns coroutines.
• Static type methods: Foo.new() to replace factory functions like new_foo().
• Smartcasting with complex conditions:if sum_type is Foo && !sum_type.is_info && get_name(sum_type.info.name) == 'foo' .
• Functions can now return fixed size arrays.
• Enum values now can have attributes.
• Generic functions as function parameters are now supported: fn f[T](x T, i int, f_ Fn[T]) T { .
• Anonymous structs can no longer have attributes.
• Allow fixed array returns.

Breaking changes

• byte deprecated in favor of u8 (byte is automatically converted to u8 by vfmt).

Checker improvements/fixes

• Disallow Result type aliases (type Foo = !Bar) and Result in maps (map[key]!Type).
• Add a missing check for taking address of literal value member.
• Fixed map initialization for maps with option values.
• Allow a << none, where a is []?&int.
• Disallow multiple else branches in a match.
• Fix index expression with sumtype of array types.
• Remove hardcoded check for function calls for C.stat, C.sigaction, etc.
• Fix multiple embedded external module interface.
• Fix missing check for diff type on map value declaration.
• Simplify error handling in the checker (#18507).
• Option alias fixes.
• Fix alias to struct ptr on struct init.
• Sumtypes can no longer hold references.
• Fix a bug checking generic closures.
• A hard to reach limit of 1 million iterations for resolving all generics.
• Fix missing check for unwrapped shift operation.
• Fix enum max value validation.
• Add a missing mutability check for array.delete calls.
• Disallow _ = <- quit.
• Disallow type matching with primitive vars.
• Warning instead of error for unnecessary brackets in if/match.
• Include import aliases when checking for import duplicates.
• Fix infering generic array type in nested call.
• Allow casted enum val and const as fixed array size.
• Disallow multiple return values in const declarations.
• Fix contains() with array of interfaces.
• Disallow mut for blank idents.

Standard library

• json: Enum value string serialization supports [json:'alias'] to change its string values.
• Struct fields can now be skipped during JSON/ORM serialization via [json:'-'] and [sql:'-'],
  in addition to [skip]. This allows having custom behavior for different serialization methods.
• builtin: heap usage API (gc_memory_use() and gc_heap_usage())
• math.big: refactoring, gcd fixes/improvements, overflow fixes, mod_inverse.
• flag: fix finalize with multiple shortargs.
• runtime: add new functions total_memory/0 and free_memory/0.
• time: small cleanup of parse_iso8601 comments, make the C.strftime declaration forwards compatible
• stbi: allow customization of number of channels in stbi.load().
• stbi: add a resize_uint8 function for resizing images in memory.
• time, x.json2: improve iso8601 time decoding.
• builtin: zero out internal map/array pointers on m.free(), to reduce the work for the GC
  mark phase for non escaping maps/arrays, used in hot loops.
• time: add more detailed error descriptions, add custom format parsing with time.parse_format.
• sync: add Mutex.destroy and RwMutex.destroy methods.
• datatypes: add Bloom filter.
• rand: add missing rand.u16(), update doc comments, add test.
• builtin: speed up string methods with vmemcpy instead of for loop for copying data.

Web

• The builtin websocket library is now thread safe.
• Enhanced builtin csrf protection in vweb.
• vweb: ability to set and get values on vweb.Context.
• vweb: support for host specific static files.
• vweb: host option added to controller, and a new host attribute.
• vweb: middleware docs improved; same with docs for [vweb_global] and shared.
• vweb: return 404 on file not found.
• net.http: copy IANA's list of methods to the http.Method enum.
• net.conv: use a pure V implementation instead of C.hton etc.
• net.html: get_tag() methods to find first tag occurrence.
• net.html: fixed text parsing for inline tags.
• net.html: fix parsing of nested quoted strings in code tags.
• picoev: FreeBSD support.

ORM

• Fixed a foreign key bug that could result in an extra insert.
• Comptime bug with [skip] and [sql:'-'] fixed.
• Checker error for unsupported field types.
• Allow structs without the id field, more flexible primary keys.
• Improved docs and examples.
• Uninitialized structs are no longer inserted into related tables.

Database drivers

• mysql: TIMESTAMP support.
• mysql: allocate memory for each string and blob dynamically depending on its value length.
• mysql: add the ability to commit transactions.

Native backend

• Refactoring, splitting large files into multiple.

C backend

• Fix code generation for generic unions.
• Fix [N]chan (fixed arrays of channels).
• Fix nested fixed array instantiation.
• Fix fixed array of map.
• Fix stringification of usize struct fields (before, they were treated as 32 bit signed numbers).

Comptime

• A new $res comptime function to get returned value in defer block (#18382).
• Fix comptimeselector option propagation.
• A mutability check for comptime assignments.
• Fix comptime assigning to sumtype or indexexpr.
• Make comptime calls work with or-block.

Tools

• A new VPM site: vpm.vlang.io. A better design, discoverability of packages, descriptions, most downloaded packages etc.
• vpm: installation of mixed modules.
• v ls --install -p D:\path\vls.exe to install a local vls executable.
• vdoc: highlight comments with gray color.
• vet: allow vetting files with global variables.
• Make util.launch_tool/3 more robust, by recompiling V tools always in a known current working folder.