What does eval catch? A function that issues a die?

It allows the execution of code which may error (ie. die) without terminating the enclosing running instance.

$ perl -E 'eval { die "Ay, caramba!"; }; say "foo"'
foo

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For instance ,open , returns undef when failing but it doesn't kill the rest of the program due to the 'exception'.

It does if you use autodie; so you might use a block eval in that situation.

Note that there are cleaner ways to trap and check for exceptions. In a recent enough perl you can use try. For older perls there are modules such as TryCatch, Try::Tiny, etc.

🦛

In reply to Re: When to use eval by hippo
in thread When to use eval by Anonymous Monk

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