"The first argument to join is not code to be executed over and over again like with map and grep. "

Agreed. But I think Loops' point is that nowhere in the documentation of join makes the above explicit.

Given:

my $str1 = $a . $x . $b . $x . $c;
my $str2 = join $x, $a, $b, $c;

[download]

You might assume they are equivalent. However, if $x is tied like in the example above, or is an overloaded object, they might not be. Given that johngg's code demonstrates that the behaviour of join in this regard has actually changed recently, it's not unreasonable to expect this behaviour to now be documented and ensured by the test suite.

toby döt ink

In reply to Re^4: Undocumented join() feature, now defunct? (++$i) by tobyink
in thread Undocumented join() feature, now defunct? by johngg

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