Copy Constructor vs Let Operator (Function Returns)

[rolliebollocks]

if i use

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     return var

the function will call the copy constructor..

what will happen if i use

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    function = var

will it call the let operator instead?

Because this can get tricky when the default constructor is bypassed (which allots some amount of memory).

I was tricked by this.

[dkl]

Yea, for Return, the result is constructed at every Return using the copy constructor or bitwise copy if there is none (I consider this latter part to be a bug, see also Copy construction behaviour).

On the other hand, for Function=, the result is constructed at the top of function using the default constructor (an error will be shown by recent fbc versions if there is none) and then each Function= does an assignment, using Let operator if it exists or bitwise copy.

Also, the compiler shows an error when mixing Return and Function= in the same function in such cases where the result is a UDT with constructors.

[rolliebollocks]

Thank you. That is good to know.

[fxm]

Obviously, when returning by reference, none constructor or let operator is called, both for 'Return' or 'Function ='.

[fxm]

These two operation cases are well summarized in documentation at KeyPgConstructor and at KeyPgOpLet.