I am calling the key() function multiple times in my code to get a value out of an array (I am using defined constants in a central file, like an application config file, which other files include).
Due to the fact I am calling key() multiple times in the same file/code I was thinking if it makes more sense to assign corresponding result once to a variable and use this one further down in the code.
I similar discussion was held for c++ (Function calls vs. local variables), but how about php7 ?
What is your experience with regards to performance and required resource ?
