UPGRADING

PHP 7.3 UPGRADE NOTES

1. Backward Incompatible Changes
2. New Features
3. Changes in SAPI modules
4. Deprecated Functionality
5. Changed Functions
6. New Functions
7. New Classes and Interfaces
8. Removed Extensions and SAPIs
9. Other Changes to Extensions
10. New Global Constants
11. Changes to INI File Handling
12. Windows Support
13. Other Changes


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1. Backward Incompatible Changes
========================================

Core:
  . The ext_skel utility has been completely redesigned with new options and 
    some old options removed. This is now written in PHP and has no external 
	dependencies.
  . Support for BeOS has been dropped.
  . Exceptions thrown due to automatic conversion of warnings into exceptions
    in EH_THROW mode (e.g. some DateTime exceptions) no longer populate
    error_get_last() state. As such, they now work the same way as manually
    thrown exceptions.

BCMath:
  . All warnings thrown by BCMath functions are now using PHP's error handling.
    Formerly some warnings have directly been written to stderr.
  . bcmul() and bcpow() now return numbers with the requested scale. Formerly,
    the returned numbers may have omitted trailing decimal zeroes.

SPL:
  . If an SPL autoloader throws an exception, following autoloaders will not be
    executed. Previously all autoloaders were executed and exceptions were
    chained.

SimpleXML:
  . Mathematic operations involving SimpleXML objects will now treat the text as
    an integer or float, whichever is more appropriate. Previously values were
    treated as integers unconditionally.

Standard:
  . getimagesize() and related functions now report the mime type of BMP images
	  as image/bmp instead of image/x-ms-bmp, since the former has been registered
		with the IANA (see RFC 7903).

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2. New Features
========================================

Core:
  . Array destructuring now supports reference assignments using the syntax
    [&$a, [$b, &$c]] = $d. The same is also supported for list().
    (RFC: https://wiki.php.net/rfc/list_reference_assignment)
  . instanceof now allows literals as the first operand,
    in which case the result is always FALSE.

BCMath:
  . bcscale() can now also be used as getter to retrieve the current scale in use.

readline:
  . Support for the completion_append_character and completion_suppress_append
    options has been added to readline_info(). These options are only available
    if PHP is linked against libreadline (rather than libedit).

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3. Changes in SAPI modules
========================================

========================================
4. Deprecated Functionality
========================================

========================================
5. Changed Functions
========================================

JSON:
  . A new flag has been added, JSON_THROW_ON_ERROR, which can be used with
    json_decode() or json_encode() and causes these functions to throw a
    JsonException upon an error, instead of setting the global error state that
    is retrieved with json_last_error(). JSON_PARTIAL_OUTPUT_ON_ERROR takes
    precedence over JSON_THROW_ON_ERROR.
    (RFC: https://wiki.php.net/rfc/json_throw_on_error)

Standard:
  . debug_zval_dump() was changed to display recursive arrays and objects
    in the same way as var_dump(). Now, it doesn't display them twice.
  . array_push() and array_unshift() can now also be called with a single
    argument, which is particularly convenient wrt. the spread operator.

PCRE:
  . preg_quote() now also escapes the '#' character.

========================================
6. New Functions
========================================

Core:
  . Added monotonic timer function hrtime([bool get_as_num]). It returns an
    array of the form [seconds, nanoseconds] with the timestamp starting at
    an unspecified point in the past. If the optional argument is passed as
    true, the return value is an integer on 64-bit systems or float on
    32-bit systems, representing the nanoseconds. The timestamp is not
    adjustable and is not related to wall clock or time of day. The timers
    are available under Linux, FreeBSD, Windows, Mac, SunOS, AIX and their
    derivatives. If no required timers are provided by a corresponding
    platform, the function returns false.

Date:
  . Added the DateTime::createFromImmutable() method, which mirrors
    DateTimeImmutable::createFromMutable().

GMP:
  . Added gmp_binomial(n, k) for calculating binomial coefficients.
  . Added gmp_lcm(a, b) for calculating the least common multiple.
  . Added gmp_perfect_power(a) to check if number is a perfect power.
  . Added gmp_kronecker(a, b) to compute the Kronecker symbol.

Intl:
  . Added void Spoofchecker::setRestrictionLevel(int $level) method, available
    when linked with ICU >= 58.1. Levels are represented as class constants
    - Spoofchecker::ASCII
    - Spoofchecker::HIGHLY_RESTRICTIVE
    - Spoofchecker::MODERATELY_RESTRICTIVE
    - Spoofchecker::MINIMALLY_RESTRICTIVE
    - Spoofchecker::UNRESTRICTIVE
    - Spoofchecker::SINGLE_SCRIPT_RESTRICTIVE
    For the detailed documentation on the restriction levels, see
    URestrictionLevel under
    http://icu-project.org/apiref/icu4c/uspoof_8h.html
  . Added Normalizer::getRawDecomposition() and normalizer_get_raw_decomposition(),
    to retrieve the Decomposition_Mapping property of a character.

Standard:
  . Added is_countable() function, to check whether a value may be passed to
    count().
    (RFC: https://wiki.php.net/rfc/is-countable)

========================================
7. New Classes and Interfaces
========================================

JSON:
  . JsonException

========================================
8. Removed Extensions and SAPIs
========================================

========================================
9. Other Changes to Extensions
========================================

 Curl:
  . libcurl >= 7.15.5 is now required.

 Filter:
  . FILTER_VALIDATE_FLOAT now also supports a `thousand` option, which
    defines the set of allowed thousand separator chars.  The default (`"',."`)
    is fully backward compatible with former PHP versions.

 FTP:
  . Set default transfer mode to binary

 ODBC: 
  . Support for ODBCRouter has been removed.
  . Support for Birdstep has been removed.

 ZIP:
  . Bundled libzip has been dropped,
    system library is now required.

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10. New Global Constants
========================================

Curl:
  . CURLOPT_REQUEST_TARGET

JSON:
  . JSON_THROW_ON_ERROR

PGSQL:
  . Requires Postgres 9.3
    - PGSQL_DIAG_SCHEMA_NAME
	- PGSQL_DIAG_TABLE_NAME
	- PGSQL_DIAG_COLUMN_NAME
	- PGSQL_DIAG_DATATYPE_NAME
	- PGSQL_DIAG_CONSTRAINT_NAME
  . Requires Postgres 9.6
    - PGSQL_DIAG_SEVERITY_NONLOCALIZED

========================================
11. Changes to INI File Handling
========================================

- birdstep.max_links
  . This INI directive has been removed.

- opcache.inherited_hack
  . This INI directive has been removed. The value has already been ignored
    since PHP 5.3.0.

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12. Windows Support
========================================

- Core
  . File descriptors are opened in shared read/write/delete mode by default.
    This effectively maps the UNIX semantics and allows to delete files with
    handles in use. It is not 100% same, some platform differences still
    persist. After the deletion, the filename entry is blocked, until all
    the opened handles to it are closed.

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13. Other Changes
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