FTFD:
In both forms, the value returned is the value of the last expression evaluated inside the mini-program; a return statement may be also used, just as with subroutines. The expression providing the return value is evaluated in void, scalar, or list context, depending on the context of the eval itself. See "wantarray" for more on how the evaluation context can be determined.

If there is a syntax error or runtime error, or a die statement is executed, an undefined value is returned by eval, and $@ is set to the error message. If there was no error, $@ is guaranteed to be a null string. Beware that using eval neither silences perl from printing warnings to STDERR, nor does it stuff the text of warning messages into $@ . To do either of those, you have to use the $SIG{__WARN__} facility, or turn off warnings inside the BLOCK or EXPR using no warnings 'all' .

1. Check for eval returning undef + $@ != null.
2. setup $SIG{__WARN__} to inform you when a warning's going to print.

In reply to Re: How many different ways can Perl code fail? by mikelieman
in thread How many different ways can Perl code fail? by Jeffrey Kegler

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