It's quite dangerous to readability to use flow control structure that are tail-loaded. As you said, they would require reading from right-to-left (or bottom-to-top), but Perl is otherwise arranged in a top-to-bottom, left-to-right order. Tail-loaded control structures are only acceptable, if ever, when the body is minimal. Your second snippet is a prime example of horrible code.

So flow control modifiers can't be tacked onto other flow control structures, including other flow control modifiers.

Correct bracketing: 

if ( $a ) { 
   print for @b;
}

[download]

The following might be an option: 

next if !$a;  # Or `return`
print for @b;

[download]

If you don't set $\ and $,, the first snippet above is equivalent to: 

print @b if $a;

[download]

In reply to Re: why not listed foreach and if? by ikegami
in thread why not listed foreach and if? by vincentaxhe

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