Only evaluate right hand side of ?? if left value is null#18
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TysonAndre wants to merge 5 commits intojaytaph:masterfrom
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Only evaluate right hand side of ?? if left value is null#18TysonAndre wants to merge 5 commits intojaytaph:masterfrom
?? if left value is null#18TysonAndre wants to merge 5 commits intojaytaph:masterfrom
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TysonAndre
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It's possible to optimize the special cases.
`reset()` wasn't used because that would emit a warning in php7 if
non-references were used.
Motivation: if the right hand size can throw,
then the transpiled code should only evaluate the right hand side
if the left hand side is `null`.
(E.g. `foo($args) ?? bar($otherargs)`, `bar` may throw)
E.g. this converts `$x = $y ?? 2` into the below expression
(`?:` is the only operator which evaluates the left hand side once
and conditionally evaluates the right hand side)
$x = (function ($v1) {
return $v1[0];
})(\call_user_func(function ($v1) {
return isset($v1) ? array($v1) : null;
}, @$y) ?: array(2));
PHPRC is explained in https://secure.php.net/manual/en/configuration.file.php#configuration.file and used only to run test cases
TysonAndre
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It's possible to optimize the special cases.
reset()wasn't used because that would emit a warning in php7 ifnon-references were used.
Motivation: if the right hand size can throw,
then the transpiled code should only evaluate the right hand side
if the left hand side is
null.(E.g.
foo($args) ?? bar($otherargs),barmay throw)E.g. this converts
$x = $y ?? 2into the below expression(
?:is the only operator which evaluates the left hand side onceand conditionally evaluates the right hand side)
EDIT: Forgot that should be call_user_func on the outside