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Even when function arguments are passed using "call by value" semantics (which is always the case in Java, and is the case by default in C#), a value of a reference type is intrinsically a reference; so if a parameter belongs to a reference type, the resulting behavior bears some resemblance to "call by reference" semantics.
In a programming language, an evaluation strategy is a set of rules for evaluating expressions. [1] The term is often used to refer to the more specific notion of a parameter-passing strategy [2] that defines the kind of value that is passed to the function for each parameter (the binding strategy) [3] and whether to evaluate the parameters of a function call, and if so in what order (the ...
In case of call by value, what is passed to the function is the value of the argument – for example, f(2) and a = 2; f(a) are equivalent calls – while in call by reference, with a variable as argument, what is passed is a reference to that variable - even though the syntax for the function call could stay the same. [5]
In programming language theory, lazy evaluation, or call-by-need, [1] is an evaluation strategy which delays the evaluation of an expression until its value is needed (non-strict evaluation) and which also avoids repeated evaluations (by the use of sharing).
Options include on the stack, in a register, or reference to something allocated on the heap. How long or complex values are handled, perhaps by splitting across multiple registers, within the stack frame, or with reference to memory. Which registers are guaranteed to have the same value when the callee returns as they did when the callee was ...
A const parameter in pass-by-reference means that the referenced value is not modified – it is part of the contract – while a const parameter in pass-by-value (or the pointer itself, in pass-by-reference) does not add anything to the interface (as the value has been copied), but indicates that internally, the function does not modify the ...
Some people (including Guido van Rossum himself) have called this parameter-passing scheme "call by object reference". An object reference means a name, and the passed reference is an "alias", i.e. a copy of the reference to the same object, just as in C/C++. The object's value may be changed in the called function with the "alias", for example:
In C, all arguments are passed by value (pass-by-reference is done by passing a pointer to a data element), so that's not a low-level question implementation question. So either "call by name, by value, or by reference" belongs here, or the lede shouldn't claim that a calling convention is just an implementation-level scheme.