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evalbytes EXPR
evalbytes

This function is similar to a string eval, except it always parses its argument (or $_ if EXPR is omitted) as a string of independent bytes.

If called when use utf8 is in effect, the string will be assumed to be encoded in UTF-8, and evalbytes will make a temporary copy to work from, downgraded to non-UTF-8. If this is not possible (because one or more characters in it require UTF-8), the evalbytes will fail with the error stored in $@.

Bytes that correspond to ASCII-range code points will have their normal meanings for operators in the string. The treatment of the other bytes depends on if the 'unicode_strings" feature is in effect.

Of course, variables that are UTF-8 and are referred to in the string retain that:

my $a = "\x{100}";
evalbytes 'print ord $a, "\n"';

prints

256

and $@ is empty.

Source filters activated within the evaluated code apply to the code itself.

evalbytes is available starting in Perl v5.16. To access it, you must say CORE::evalbytes, but you can omit the CORE:: if the "evalbytes" feature is enabled. This is enabled automatically with a use v5.16 (or higher) declaration in the current scope.