for (...) {
    if (...) {
        ...
    }
}

##</code><code>##

for (...) {
    next unless ...;
    ...
}

##</code><code>##

... if ...;

##</code><code>##

if (...) {...;}

##</code><code>##

SCANNING: while (...) {
    ...
    for (...) {
        ...
        next SCANNING if ...;
    }

    ...
}