Hi vr,

...unexpected is that this "next unless" thing is actually valid and does return value

I'm sorry but I don't understand where you get that next unless returns a value?

next is just like a continue statement in C. If it is called, it just jumps out of whatever it is doing and transfers control to the for loop.

... || next is AFAICS 100% equivalent to next unless ...

In your for loop you go through a scalar reference to 0 so the scalar that is tested is NOT 0 (or in other words NOT false). The value is valid so the next is not executed. The value is dereferenced to 0 and is printed to the console. The next loop you execute is with the value 0 and in the statement is interpreted as 0 (or in other words false). So the || statement will execute the next command which is next ;. All execution is interrupted and control is transferred to for and nothing is printed.

I hope this makes sense

Veltro

Edit: One more thing that I noticed:

next unless exists $ht-> { Default };

is not the same as:

... ->{ Default } || next

In the first fragment next will only be executed in case the Default value does not exists. In case ...->{ Default } returns 0 then next will also be excuted. So be carefull with that.

In reply to Re: Abuse of "or next" in expressions and "next" that returns value by Veltro
in thread Abuse of "or next" in expressions and "next" that returns value by vr

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