Roadmap

VHP is being developed incrementally, with each phase adding new capabilities while maintaining backwards compatibility.

Development Phases

Phase	Status	Features
1. Variables & Operators	✅ Complete	Variables, assignment, arithmetic, comparison, logical, ternary, null coalescing
2. Control Flow	✅ Complete	if/else, while, for, do-while, switch, break/continue
3. Functions	✅ Complete	Declarations, calls, returns, parameters, 50+ built-ins
4. Arrays	✅ Complete	Literals, access, modification, foreach, 15 array functions
5. Classes & Objects	✅ Complete	Classes, properties, methods, constructors, inheritance, interfaces, traits, readonly, property hooks, cloning
6. Modern PHP 8.x Features	✅ Complete	Match Expressions ✅, Named Arguments ✅, Attributes ✅, Enums ✅, Pipe Operator ✅, Fibers ✅
7. PHP Core Language	🔄 In Progress	Exceptions ✅, Type System ✅ (runtime validation), Namespaces, Generators, Abstract/Final ✅, Magic Methods
8. PHP 8.5 Features	🔄 In Progress	URI Extension, Clone with syntax, #[\NoDiscard], array_first/last ✅, Closures in constants
9. Standard Library	📋 Planned	PCRE regex, sorting, array_map/filter/reduce, JSON, DateTime, file system functions

Phase Details

Phase 1: Variables & Operators ✅

• Variables ($name)
• Assignment (=) and compound assignment (+=, -=, etc.)
• Arithmetic operators (+, -, *, /, %, **)
• String concatenation (.)
• Comparison operators (==, ===, !=, !==, <, >, <=, >=, <=>)
• Logical operators (&&, ||, !, and, or, xor)
• Null coalescing (??)
• Ternary operator (? :)
• Increment/decrement (++, --)

Phase 2: Control Flow ✅

• if/elseif/else statements
• while loops
• do…while loops
• for loops
• foreach loops (syntax parsing - requires arrays for full support)
• switch/case/default
• break/continue

Phase 3: Functions ✅

• Function declarations
• Function calls
• Return statements
• Parameters (by value, by reference)
• Default parameter values
• 50+ built-in functions

Phase 4: Arrays ✅

• Array literals ([1, 2, 3])
• Associative arrays (["key" => "value"])
• Array access ($arr[0], $arr['key'])
• Array modification and append ($arr[] = value)
• foreach with arrays (value only and key-value)
• 13 array functions (count, array_push, array_pop, in_array, array_keys, array_values, array_merge, array_reverse, array_search, array_key_exists, range, etc.)

Phase 5: Classes & Objects ✅

• Class declarations with class keyword
• Properties with visibility modifiers (public, private, protected)
• Methods with $this reference
• Constructors (__construct)
• Object instantiation with new
• Property access ($obj->property)
• Method calls ($obj->method())
• Static method calls (ClassName::method())
• Default property values
• Multiple objects from same class
• Inheritance (extends) with property/method inheritance and parent:: calls
• Interfaces with method signatures and constants
• Interface inheritance (extends Interface1, Interface2)
• Class implementation of interfaces (implements Interface1, Interface2)
• Traits with properties and methods
• Trait composition in classes (use Trait1, Trait2)
• Trait conflict resolution (insteadof, as)
• Traits using other traits
• Constructor Property Promotion (PHP 8.0)
• Readonly Properties (PHP 8.1)
• Readonly Classes (PHP 8.2)
• Property hooks with get/set (PHP 8.4)
• Object cloning with clone keyword (PHP 5.0)
• Clone with property modification syntax (PHP 8.4)

Phase 6: Modern PHP 8.x Features 🚧

This phase focuses on catching up with major features introduced in PHP 8.0 and beyond.

• ✅ Match Expressions (PHP 8.0) - A more powerful and safer alternative to switch.
• ✅ Named Arguments (PHP 8.0) - Pass arguments to functions based on parameter names.
• ✅ Attributes (PHP 8.0) - Structured metadata syntax parsing and AST storage. Full reflection API support.
• ✅ Enums (PHP 8.1) - Pure and backed enums with case access, properties, and built-in methods (cases(), from(), tryFrom()).
• ✅ Pipe Operator (PHP 8.5) - Functional-style operator for chaining function calls with left-to-right flow.
• ✅ Fibers (PHP 8.1) - The foundation for lightweight, cooperative concurrency (async/await).

Phase 7: PHP Core Language Compatibility 📋

This phase focuses on implementing core PHP language features that are essential for PHP compatibility. These features have been part of PHP for many versions and are fundamental to running most PHP code.

Exception Handling ✅

• try/catch statements - Basic exception handling with catch blocks
• throw keyword - Throwing exceptions
• finally blocks - Code that always executes regardless of exceptions
• Exception class - The base exception class with getMessage() and getCode() methods
• Multiple catch blocks - Catching different exception types
• Multi-catch (PHP 7.1) - Catching multiple exception types in one block catch (TypeA | TypeB $e)
• Throw expression (PHP 8.0) - Using throw in expressions (arrow functions, null coalesce, ternary)

Type System ✅

• Type declarations - Parameter and return type hints (int, string, float, bool, array, callable, object, iterable, mixed)
• Nullable types (PHP 7.1) - ?int, ?string syntax
• Union types (PHP 8.0) - int|string, int|null
• Intersection types (PHP 8.1) - Iterator&Countable
• DNF types (PHP 8.2) - Disjunctive Normal Form (A&B)|C, (A&B)|(C&D)
• void return type (PHP 7.1) - Functions that return nothing
• never return type (PHP 8.1) - Functions that never return (throw or exit)
• static return type (PHP 8.0) - Return type for late static binding
• Runtime type validation - Full enforcement of parameter and return types
• Class type hints - Custom class/interface types
• true/false/null as standalone types (PHP 8.2)

Namespaces

• namespace declaration - namespace App\Controllers;
• use statements - use App\Models\User;
• use aliases - use App\Models\User as UserModel;
• Group use declarations (PHP 7.0) - use App\Models\{User, Post};
• Global namespace fallback - \strlen(), \Exception
• Namespace constants - namespace\CONST_NAME

Generators & Iterators

• yield keyword - Generator syntax
• yield from (PHP 7.0) - Generator delegation
• Generator return values (PHP 7.0) - return in generators
• Iterator interface - Custom iterators
• IteratorAggregate - Objects that return iterators

Abstract & Final

• abstract classes - Classes that cannot be instantiated ✅
• abstract methods - Methods that must be implemented by subclasses ✅
• final classes - Classes that cannot be extended ✅
• final methods - Methods that cannot be overridden ✅
• final constants (PHP 8.1) - Constants that cannot be overridden

Magic Methods

• __toString() - String representation of objects ✅
• __invoke() - Callable objects ✅
• __get()/__set() - Property overloading ✅
• __isset()/__unset() - Property checking ✅
• __call()/__callStatic() - Method overloading ✅
• __clone() - Custom clone behavior ✅
• __debugInfo() - Custom var_dump output
• __sleep()/__wakeup() - Serialization hooks
• __serialize()/__unserialize() (PHP 7.4) - Modern serialization

Additional OOP Features

• Anonymous classes (PHP 7.0) - new class { ... }
• Property hooks (PHP 8.4) - get/set accessors on properties
• Static properties (PHP 5.0) - static $property with visibility modifiers
• Late static binding (PHP 5.3) - static::, self::, parent::
• Readonly static properties (PHP 8.3) - Immutable class-level properties
• Asymmetric visibility (PHP 8.4) - public private(set), public protected(set), protected private(set) for both instance and static properties
• #[\Override] attribute (PHP 8.3) - Marking overridden methods with validation
• Object comparison - == vs === for objects
• Covariance & Contravariance (PHP 7.4) - LSP-compatible type widening/narrowing
• Constants in traits (PHP 8.2)

Control Flow Additions

• Alternative syntax - if:, endif;, foreach:, endforeach;, etc. ✅
• goto statement - Jump to label
• declare directive - declare(strict_types=1); ✅

Function Features

• Arrow functions (PHP 7.4) - fn($x) => $x * 2 ✅
• Variadic functions - function f(...$args)
• Argument unpacking - f(...$array)
• First-class callables (PHP 8.1) - $fn = strlen(...) ✅
• Closures in constants (PHP 8.5) - Static closures in constant expressions

Phase 8: PHP 8.5 New Features 📋

Features from the latest PHP release that VHP should support to be a true PHP 8.5 superset.

• URI Extension (PHP 8.5) - Built-in URI/URL parsing and manipulation via Uri\Rfc3986\Uri class
• Clone with syntax (PHP 8.5) - clone($obj, ['prop' => 'value']) syntax (VHP has basic clone)
• #[\NoDiscard] attribute (PHP 8.5) - Warn when return values are ignored
• Closures in constant expressions (PHP 8.5) - Static closures in attributes and defaults
• First-class callables in constants (PHP 8.5) - strlen(...) in constant expressions
• array_first() / array_last() (PHP 8.5) - Get first/last element of array
• #[\DelayedTargetValidation] (PHP 8.5) - Delay attribute target validation
• Final property promotion (PHP 8.5) - final in constructor property promotion
• Attributes on constants (PHP 8.5) - Apply attributes to constants
• Error backtraces (PHP 8.5) - Fatal errors include backtraces

Phase 9: Standard Library Expansion 📋

Expanding built-in functions to match PHP’s standard library.

String Functions (missing)

• sprintf format specifiers: %d, %s, %f, %x, %b, padding, precision
• sscanf, fprintf, vprintf, vsprintf
• preg_match, preg_match_all, preg_replace, preg_split (PCRE)
• str_split, chunk_split, wordwrap
• str_shuffle, str_word_count
• number_format, money_format
• html_entity_decode, htmlentities, htmlspecialchars, htmlspecialchars_decode
• strip_tags, addslashes, stripslashes
• quoted_printable_encode, quoted_printable_decode
• convert_uuencode, convert_uudecode
• ctype_* functions (ctype_alpha, ctype_digit, etc.)

Array Functions (missing)

• array_map, array_filter, array_reduce, array_walk
• array_slice, array_splice, array_chunk
• array_combine, array_fill, array_fill_keys
• array_flip, array_unique, array_count_values
• array_diff, array_diff_key, array_diff_assoc
• array_intersect, array_intersect_key, array_intersect_assoc
• array_column, array_multisort
• sort, rsort, asort, arsort, ksort, krsort, usort, uasort, uksort
• shuffle, array_rand
• array_pad, array_product, array_sum
• list() assignment, extract(), compact()

Math Functions (missing)

• log, log10, log1p, exp, expm1
• sin, cos, tan, asin, acos, atan, atan2
• sinh, cosh, tanh, asinh, acosh, atanh
• fmod, intdiv, fdiv
• pi, M_PI, M_E constants
• hypot, deg2rad, rad2deg
• base_convert, bindec, octdec, hexdec, decbin, decoct, dechex
• is_nan, is_finite, is_infinite

Date/Time Functions

• time, mktime, strtotime
• date, gmdate, strftime
• DateTime class and related classes
• DateTimeImmutable, DateInterval, DatePeriod

JSON Functions

• json_encode, json_decode
• json_last_error, json_last_error_msg
• JSON_* constants

File System Functions

• file_get_contents, file_put_contents
• fopen, fclose, fread, fwrite, fgets
• file_exists, is_file, is_dir, is_readable, is_writable
• mkdir, rmdir, unlink, rename, copy
• glob, scandir, readdir
• realpath, dirname, basename, pathinfo

Miscellaneous

• class_exists, interface_exists, trait_exists, function_exists
• get_class, get_parent_class, is_a, is_subclass_of
• method_exists, property_exists
• call_user_func, call_user_func_array
• constant, define, defined

Contributing to the Roadmap

Have ideas for VHP? Feel free to:

• Open an issue to discuss new features
• Submit a pull request with an implementation
• Join the discussion on existing roadmap items