It applies to for loops.

for (1..3) { ... }
for (@a) { ... }
for (my $i=10; $i--; ) { ... }
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It applies to while and until loops.

while (f()) { ... }
until (f()) { ... }
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It applies to bare loops.

{ ... }
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It does NOT apply to conditional statements.

if (f()) { ... }
unless (f()) { ... }
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It does NOT apply to statement modifiers.

... while f();    Including: do { ... } while f();
... for @a;
... if f();
etc
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It does NOT apply loop-like functions.

grep { ... } @a
map { ... } @a
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