floating-point numbers have rounding errors and our decimal system isn't too compatible to binary representation

DB<8> printf '%.20f', 0.688 + 0.289 + 0.023
0.99999999999999989000

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so $var != 1

Perl's DWIM is sometimes trying to round the string representation, that's why eq seemingly "works".

Rule of thumb, add integers and correct afterwards to the right magnitude.

  DB<15> p 1 == (688 + 289 + 23) /1000
1

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see also Humans have too many fingers

Cheers Rolf
(addicted to the Perl Programming Language :)
Wikisyntax for the Monastery FootballPerl is like chess, only without the dice

In reply to Re: $var == 1 fails when $var = 1 by LanX
in thread $var == 1 fails when $var = 1 by mjlush

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