Be aware that most Perl experts discourage the use of string eval. For example:

• merlyn in •Re^2: Dynamically constructed function calls states: Do not resort to eval-string if other means are available. You're firing up the compiler (slower than almost any other solution), and exposing yourself to hard to debug and hard to secure practices.
• In this quiz of the week MJD states: A good rule of thumb is that unless what you're trying to do is most clearly described as "compile and run arbitrary Perl code", it's probably a mistake to use 'eval' to do it.
• Perl Best Practices, Chapter 8, has a guideline titled: Avoid string eval. Conway argues that string eval can be slow; produces run time warnings rather than more desirable compile time warnings; and code that generates other code tends to be harder to maintain.

While string eval should be avoided, block eval (spelled try with perl 5.40+) is fine, as described here.

References Added Later

• Re^3: Create sort function from a text file (string eval vs block eval) by me (2021)

• The safety of string eval and block eval. by TrixieTang (2016)
• Re^4: The safety of string eval and block eval. by afoken (2016)
• Undumping Perl by haukex (2016)

• Loading PERL Module from scalar in RAM? by AssetXero (2023)

• trouble with packages/eval/variable-scoping by Ratazong (2024)
• Re: trouble with packages/eval/variable-scoping by afoken (2024) - Imagine someone changing xxx.ptysav to contain $_=`rm -rf /`;. That would be a bad day for you.
• Re^3: trouble with packages/eval/variable-scoping by hippo (2024) - Config files should be parsed, not executed
• Re^2: passing newline in string argument by haukex (2025) - "I think it's very well worth mentioning that eval is a massive security hole with untrusted input"

See Also

• Re: eval to replace die? (Exceptions and Error Handling References)

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