adapt constant expressions

[xerc]

https://wiki.php.net/rfc/calls_in_constant_expressions

[aimeos]

Why is the backslash before PHP functions necessary?

[xerc]

for safety; "ensure that the function called is from the global namespace, even if there is a function by the same name in the current namespace" https://stackoverflow.com/questions/4790020/#answer-4790031

[xerc]

(?<![\w\.\\>:])(abs|acosh|acos|array_chunk|array_column|array_count_values|array_diff_assoc|array_diff_key|array_diff|array_fill_keys|array_fill|array_flip|array_intersect_assoc|array_intersect_key|array_intersect|array_key_exists|array_key_first|array_key_last|array_keys|array_merge_recursive|array_merge|array_pad|array_product|array_replace_recursive|array_replace|array_reverse|array_search|array_slice|array_sum|array_unique|array_values|asinh|asin|atan2|atanh|atan|boolval|ceil|checkdate|chr|cosh|cos|count|decbin|dechex|decoct|deg2rad|doubleval|expm1|exp|floatval|floor|fmod|gettype|gmmktime|hash_algos|hypot|in_array|intdiv|intval|is_array|is_bool|is_countable|is_double|is_finite|is_float|is_infinite|is_integer|is_int|is_iterable|is_long|is_nan|is_null|is_numeric|is_object|is_real|is_resource|is_scalar|is_string|log10|log1p|log|max|min|pi|pow|rad2deg|range|round|sinh|sin|sizeof|sqrt|tanh|tan)(?=\s*\()
=> \\$1

[aimeos]

This is not necessary because there are almost no functions in Aimeos and if yes, they are prefixed by ai.
In general, we are currently trying to simplify the code base as much as possible and avoid anything which is not really necessary.

[xerc]

ok ; than you should check for negations as in 32c0c3e