Re: Re: Re: has it been blessed?

[chipmunk]

Efficiency is nice, but there's something to be said for correctness as well. You've also forgotten REF, CODE, and LVALUE.

Comparing the return value from ref to a list of known types is simply the wrong approach. Either you'll forget something, or a new type will be added in a future version and your code will break.

Go with the UNIVERSAL::isa() approach. Really.

[rjray]

I agree, but to clarify, the best approach would seem to be:

    if (ref($obj) and UNIVERSAL::isa($obj, 'UNIVERSAL')) {
        ...
    }

Well, "best" in absence of the blessed primitive, of course...

--rjray

[dragonchild]

if (UNIVERSAL::isa($obj, 'UNIVERSAL')) { is more than enough. If it's not a reference, UNIVERSAL::isa() will return undef. Don't bother doing a check twice.

------
We are the carpenters and bricklayers of the Information Age.

Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.

[rjray]

The reason I wrote it that way is that ref($obj) is a single-opcode operation, much less expensive than the execution of UNIVERSAL::isa($obj, 'UNIVERSAL'). Unless you know for certain that the value being tested will a reference the majority of the time, then you can save a reasonable amount of execution time with ref() coupled with the short-circuiting and operator. I stand behind this one.

--rjray

[chipmunk]

UNIVERSAL::isa($obj, 'UNIVERSAL') will also return true if $obj is the string 'UNIVERSAL', so the ref check is actually useful.