You can return from it. Modifications to @_ inside a BEGIN block disappear after leaving the BEGIN block. Also, (caller(0))[3] returns "main::BEGIN" inside BEGIN blocks.

    # Prints nothing
    BEGIN { @_ = 1 }
    print @_;


    # Prints 1
    BEGIN {
        print 1;
        return;
        print 2;
    }


    # Prints main::BEGIN
    BEGIN { print +(caller(0))[3] }


    # (Un)expectedly, this won't recurse
    BEGIN { &BEGIN }
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I'd say it behaves quite a bit like a subroutine, albeit not completely.

ihb

Read argumentation in its context!