We have operator and operands, function and formal arguments. Is the difference purely lexical (we use alphanumerics for funciton identifiers but identify operators with special characters, e.g. "+" and ">=") or it is syntactical, like I guessed here
f(a,b) -- prefix notation used for functions a.f(b) -- infix notation for method invocation (used in OOP) a f b -- infix notation without dot and parenthesis used in operator invocations
so that when we write
a + b we have an operator but
"+"(a, b) (both ways are acceptable in VHDL) makes it a function? Do tools treat them differently? Can you differentiate them? Can you say that this is not a function, it is an operator or vice-verse? When I read the definitions in wikipedia, I do not see that syntax is a distinguishing feature of a concept. So, is it right that operators and functions are synonyms, two different words for the same thing, same meaning, same notion? I have such guess but have never seen it stated explicitly. Please agree with my guess or say what is the difference.