<entry index='e'>
<name>Exception</name>
<reference>thread</reference>
<reference>ruby</reference>
<content>
    The one occurs in exceptional situation.
    when it occurs,
    unless it is caught explicitly by '((|rescue|))' paragraph of '((|begin|))',
    the call hierarchy is traced back
    and the execution of program (((Thread))) is interrupted.
    The ((Ruby)) program should thank exception,
    because it is able to ((end)) without checking
    an exceptional situation one by one, in almost all of the case.
    The information on the place where the exception is generated
    is stored in ((|$@|)),
    and the information on the exception itself is stored in ((|$!|)).
</content>
</entry>
