I don't see why this should be an error. Just as

my $x = 5 if $t;

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could be semantically equivalent to

my $x; $x = 5 if $t;

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I think it all boils down to a matter of personal interpretation and taste; your example doesn't convince me at all: yes, it could, but I see no reason why it should. More precisely, it's true that the single

my $x = 5;

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statement is semantically equivalent to the two

my $x;
$x = 5;

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statements. But is it true in general than when STATEMENT is equivalent to STATEMENT1; STATEMENT2; ... STATEMENTn; then also 

STATEMENT if condition;

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is equivalent to

STATEMENT1;
STATEMENT2;
...
STATEMENTn if condition;  # ?!?

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IMHO not only is the answer no but FWIW I see no aesthetical appeal of such an "algebraic" property.

OTOH since

STATEMENT if condition;

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is generally equivalent to

if (condition) { STATEMENT }

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and

if ($t) { my $x = 5 }

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is perfectly valid, albeit fundamentally useless, perhaps the "incriminated" construct should not trigger an error, but just be a happily useless thingy. Granted, Perl 5 already has so many ad hoc deviations from orthogonality for the sake of beauty, pragmatics and magic that one may want to throw in yet another one: yet I still fail to see how that particular construct could be of any good with any of those.

In reply to Re^5: Curious result of using "my ... if ..." by blazar
in thread Curious result of using "my ... if ..." by jrw

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