Clearly, this is just a prototypical example of why you can never (in any programming language other than COBOL) test a fractional number for “exact equality.”

Only if by "fractional number" you actually mean floating-point number. It works fine with actual fractional numbers:

$ perl6 -e 'say 10 + 14.4 - 10 == 14.4'
True
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(Perl 6 stores those as actual fractions, and does exact math with them; you only get floating points if the fractions overflow, or if you request them with the scientific notation 14.4e0).