How to know the predefined parameter in php functions? - php

Question

If there is 2 parameter in php function how to know which parameter is kept in first and another second.
This is a php function array_search($needle,$array). This will search $needle in an array $array.
In array_slice($array, 2) slice is to be done in an array $array is first parameter.
In trim($string, 'abc') trim is to be done in string $string is a first parameter.
Is there any way to remember which parameter come first? I think we can remember function but remembering parameter also is not possible for all functions.
Thanks

Answer 1

Welcome to PHP ,
The likely most common complaint you get to hear about PHP is the
inconsistent and unclear naming of functions in the standard library,
as well as the equally inconsistent and unclear order of parameters.
Some typical examples:
// different naming conventions
strpos
str_replace
// totally unclear names
strcspn // STRing Complement SPaN
strpbrk // STRing Pointer BReaK
// inverted parameter order
strpos($haystack, $needle)
array_search($needle, $haystack)
so if you want to check (within your application and away from man pages)
as a work around to get around this, you may make use of Reflection collection in php :
for example:
function getFunctionInfo($functionName) {
$function = new ReflectionFunction($functionName);
return [
'name' => $function->getName(),
'parameters' => array_column($function->getParameters(), 'name'),
'numberOfParameters' => $function->getNumberOfParameters(),
'requiredParameters' => $function->getNumberOfRequiredParameters()
];
}
print_r(getFunctionInfo('explode'));
this will output:
Array (
[name] => explode
[parameters] => Array (
[0] => separator
[1] => str
[2] => limit
)
[numberOfParameters] => 3
[requiredParameters] => 2
)
and for live view: https://3v4l.org/T2Nad
the above quote had been quoted from : nikic.github.io