Copying Rob's one-liner into my system gives yet another answer:
-1+1.22464679914735e-16i

That's the same result as the OP got.
The difference is that perl's print function rounded the final 2 digits away, whereas Raku's didn't.
Now that I'm back home, I can see the same with perl on Ubuntu-20.04.
The figure that I reported came from Windows, so there's a discrepancy in the underlying C libraries. 
C:\>perl -le "printf '%a',  1.2246467991473532e-16;
0x1.1a62633145c07p-53
C:\>perl -le "printf '%a',  1.2246063538223773e-16;
0x1.1a6p-53

[download]
The latter (which is what windows is reporting) is suspiciously truncated.

With the MPC library, the given inputs produce a result of -1+2.8954204500590832e-16.

Cheers,
Rob

In reply to Re^5: Euler's identity in Raku by syphilis
in thread Euler's identity in Raku by tomasz

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