clamp() keeps values inside a range
Use clamp() when user input, percentages,
ratings, or layout values must stay between a lower and
upper bound.
SortDirection makes sort APIs type-safe
PHP 8.6 adds a global SortDirection unit enum
with Ascending and
Descending cases.
Reflection can ask whether a property is readable or writable
ReflectionProperty::isReadable() and
isWritable() account for readonly and
asymmetric visibility rules that
isPublic() cannot express.
Enums can customize var_dump()
Enums may now implement __debugInfo(), so
debugging output can show the domain-specific details you
care about.
trim() now removes form feed by default
PHP 8.6 treats \f like other default whitespace
in trim(), ltrim(),
rtrim(), and chop().