Because decimals alone are special inside string literals. perldata states:

Hexadecimal, octal, or binary, representations in string literals (e.g. '0xff') are not automatically converted to their integer representation. The hex() and oct() functions make these conversions for you. See hex and oct for more details.

Consider the decimal autoconversion as a bit of handy magic, nothing more.

In reply to Re^3: why are hex values not numbers? by hippo
in thread why are hex values not numbers? by perl-diddler

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