Perl 5 has several places where it allows either a (possibly compound) statement, or a block. For example, 

@array = grep $_ != 1, @array;
@array = grep{ $_ != 1 } @array;


@array = map ++$_, @array;
@array = mapp{ ++$_ } @array;

print for 1 .. 10;
for( 1 .. 10 ) {
    print;
}

push @a, $_ while <FH>;
while( <FH> ) {
    push @a, $_;
}

[download]

Ignoring any performance difference that might come from avoiding an extra level of scope, is anyone aware of any piece of code that would run unchanged as a statement or a block, that would behave differently in one relative to the other?

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In reply to statement vs. block? by BrowserUk

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