As I understand it, the standard "list in scalar context" behavior is "size of the list".

No, no. The incorrect assumption you are supposed to make at this point is that a "list in scalar context" returns "the last item" (by default). But both assumptions are wrong. Each "operation that would return a list of scalars if called in a list context" makes its own, customized decision about what it will return in a scalar context and those two are just the most common choices (and "last item" is even more common than "number of items").

There is no default choice. @x returns the size of the array. ( $x, $y, z() ) returns the value of z() (called from a scalar context). %h returns the bucket usage. Something I can't remember returns the first item. sort returns nothing useful (and does nothing useful to boot).

Now a less "idiomatic" way to getting the size of an arbitrary list might be worth having. You didn't express it this way because of your wrong assumption about this being "the default" list-to-scalar conversion. So I'd rename the keyword "count" or such instead of "list", at which point it makes sense.

- tye        


In reply to Re^3: What's most efficient way to get list context? (count) by tye
in thread What's most efficient way to get list context? by tlm

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