Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:122488
Message-ID: <4e05c798-1b09-4f88-9cce-586e3138bd4b@mabe.berlin>
Date: Sun, 25 Feb 2024 13:25:12 +0100
Precedence: bulk
MIME-Version: 1.0
User-Agent: Mozilla Thunderbird
Subject: Re: [PHP-DEV] [RFC][Discussion] Raising zero to the power of negative
 number
To: internals@lists.php.net
References: <CAPTD5yHW=kUcDpboNeb07uGHFnEzbGCxycFoAb81bFTKEDCW4Q@mail.gmail.com>
 <CAO__Xv6NoJ2g9_5KMWVc73aB9xdNX+jvECtOgQp=QAU2x8-3pw@mail.gmail.com>
 <npf3tNZ9UgrhArIomR4tM71JGJyRfo2ZAerxmFtO2BS7lDfbsjhM60A_DI3L_1PGEuRh28t7f-3mXCq0Wa1etkHVZiaK9bizyv1NDaicXvE=@gpb.moe>
 <CAPTD5yHqydNOBA_GTtQRf8XLA-TLdocYAAhLSK-zXAPdgo+rpQ@mail.gmail.com>
Content-Language: en-US
Autocrypt: addr=marc@mabe.berlin; keydata=
 xsBNBFby8roBCAD4qHjbk9+V3SmB5DfpkTtX58jYJ9VXVfF54MDoI0fQiYvKyrrghfO78alH
 c12RsEZxLH2F5kEfu8WO4wA4apg2gBnRRxqPj7krsct1ySOAdMrRVp8Wtaeaznpdcn2gJZyA
 MSI6LTzebT25N77ksvSrUi1BuCKyOa7SmYff3xGgOwYsHQlT5opMNGPCVegiPmO/K37anwts
 gj6L7RVtjXtp2Z3wAs6r3EmO318PL48xDLUgYMvEFAPJglth5FGH2En6n6HFIhxh43LqXQiN
 eHVjLjS2y8huNBswwc9ZVxk3ip5z/GCmpWnNkgGBOSJ7loJRsq2tOaU6yU8KWb5rhOoFABEB
 AAHNIU1hcmMgQmVubmV3aXR6IDxtYXJjQG1hYmUuYmVybGluPsLAeAQTAQIAIgUCVvLyugIb
 AwYLCQgHAwIGFQgCCQoLBBYCAwECHgECF4AACgkQOTar91O8iM6jzggAwvV6MqU/hcAI6ldp
 xVjucGz2J9cAWtva8GL+rm9zvEs7EENtamehJiZob/CTw50WiI/zsJzPblktpT0D2AFBEp9k
 P5/8CmCpZzxYPsxnLtsFM52fOBpO+aP0PSStBpJjndjBH7HPqKcTCXM3ZM+SL6lyRweAJR7G
 +JXIZbuUrbjB2lbGx3itNZ6TeXqqnE6KTXNKLEbNHfVdzE4sPDkmuZRo/M2h+gmeS1iQb29W
 BmhvL6czugCQI9rYl7C4Nci9wPii1lTYyfCWQfQKID4/F2HiOv+N/vDMCK1xV8TUeCy8w4X+
 nYj+wDog046ki9lUM60oPij6WoSJLqfsXr1kNc7ATQRW8vK6AQgAq7QYLB1Dz+8RSi5AGJP1
 tOFQXtcxyOhNVQZsI1mCQiHay4wteQ+5m4EOUuR+FrFIlnbSrPdTkKD2wvQDHVqpZivThBpJ
 vara/ick0wi2R3dasu1sPMu1P6h1EwUsydhviNJB07aLfPAWD6eoqmGTd8236znIIq7mbnNp
 OnxIQxviTyELUekrNw38uQtVzR6XZv9PAThA2o1J1JZID7QUpKcNyo9ebYlwxyS+xzhA4DLD
 qfD6O5sKoKvxEf2fIZeP0ETPpHNYk0WiWnmNoPy8eEY07LriYALVidBwPBcxus0wGoKf8Nun
 y2aE13SHmj0ioBI1bXMGJx3hEbvzXK6WrwARAQABwsBfBBgBAgAJBQJW8vK6AhsMAAoJEDk2
 q/dTvIjOkowIAI70P8U4j3eqyK/7x1bnCZZRcpwZ1aH+LR1yMKTINo9NDqlOBWQTLT69YMfV
 4UN+nTSiD/uLw1fSeLSzBwpoalCMLPVOX/d3Mq5JtL5cKtWUTIVf3Vb7VbN4Rvb8HgWjeSnM
 1PiG9yQBmLKI68sG/gdgvA/xANdUatkDgG0yj8PCdt+Vy4EblXbIAXZXJ6eRugSKowTjst7i
 HXKOJxivomHFcmqmkiqjwGTGx/jrhbDtEpPDRk+U9W45D4CbUcyPR6lMSrje5JPGQDv/45M5
 wPe286YelBjnb0cWRJpA7GZCWDKZOsQ2H6cCRBi8i4m+vfRk7GLA536XnmvWxKFVP9U=
In-Reply-To: <CAPTD5yHqydNOBA_GTtQRf8XLA-TLdocYAAhLSK-zXAPdgo+rpQ@mail.gmail.com>
Content-Type: multipart/signed; micalg=pgp-sha256;
 protocol="application/pgp-signature";
 boundary="------------mKqM74x7iLKM3nHRupxXGOUL"
From: marc@mabe.berlin (Marc Bennewitz)

This is an OpenPGP/MIME signed message (RFC 4880 and 3156)
--------------mKqM74x7iLKM3nHRupxXGOUL
Content-Type: multipart/mixed; boundary="------------1j7EtL1Pckv32xDx0X4in3ig";
 protected-headers="v1"
From: Marc Bennewitz <marc@mabe.berlin>
To: internals@lists.php.net
Message-ID: <4e05c798-1b09-4f88-9cce-586e3138bd4b@mabe.berlin>
Subject: Re: [PHP-DEV] [RFC][Discussion] Raising zero to the power of negative
 number
References: <CAPTD5yHW=kUcDpboNeb07uGHFnEzbGCxycFoAb81bFTKEDCW4Q@mail.gmail.com>
 <CAO__Xv6NoJ2g9_5KMWVc73aB9xdNX+jvECtOgQp=QAU2x8-3pw@mail.gmail.com>
 <npf3tNZ9UgrhArIomR4tM71JGJyRfo2ZAerxmFtO2BS7lDfbsjhM60A_DI3L_1PGEuRh28t7f-3mXCq0Wa1etkHVZiaK9bizyv1NDaicXvE=@gpb.moe>
 <CAPTD5yHqydNOBA_GTtQRf8XLA-TLdocYAAhLSK-zXAPdgo+rpQ@mail.gmail.com>
In-Reply-To: <CAPTD5yHqydNOBA_GTtQRf8XLA-TLdocYAAhLSK-zXAPdgo+rpQ@mail.gmail.com>

--------------1j7EtL1Pckv32xDx0X4in3ig
Content-Type: multipart/mixed; boundary="------------oiintvTFZ3ryqlelIV0Lx4Vh"

--------------oiintvTFZ3ryqlelIV0Lx4Vh
Content-Type: multipart/alternative;
 boundary="------------ua81tOZZCoOqu18mdhnMoo4a"

--------------ua81tOZZCoOqu18mdhnMoo4a
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: base64
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--------------ua81tOZZCoOqu18mdhnMoo4a
Content-Type: text/html; charset=UTF-8
Content-Transfer-Encoding: quoted-printable

<!DOCTYPE html>
<html>
  <head>
    <meta http-equiv=3D"Content-Type" content=3D"text/html; charset=3DUTF=
-8">
  </head>
  <body>
    <p>Hi Jorg,<br>
    </p>
    <div class=3D"moz-cite-prefix">On 13.01.24 00:25, Jorg Sowa wrote:<br=
>
    </div>
    <blockquote type=3D"cite"
cite=3D"mid:CAPTD5yHqydNOBA_GTtQRf8XLA-TLdocYAAhLSK-zXAPdgo+rpQ@mail.gmai=
l.com">
      <pre class=3D"moz-quote-pre" wrap=3D"">Thank you for the suggestion=
s. I agree that error message should be more
meaningful. I changed it.

The main driver of this change is to match the division by zero behavior
for both operators which can operate on both integers and floats. Would i=
t
make sense to create a function `fpow` similarly to `fdiv` for the correc=
t
IEEE 754 logic?</pre>
    </blockquote>
    <p>As of your note of consistent behavior here, in your RFC I don't
      see any note about operating on float - It's all about int. It
      would be good to explicitly describe both int and float behavior
      in your RFC.<br>
    </p>
    <p>About `<span style=3D"white-space: pre-wrap">fpow` - I personally =
never felled the need to use `fdiv` but as `fdiv` was explicitly introduc=
ed to expose </span>IEEE-754
      semantics I think it totally makes sense to add `fpow` as well.</p>=

    <p>Greetings,<br>
      Marc<br>
    </p>
    <p><span style=3D"white-space: pre-wrap">
</span></p>
    <blockquote type=3D"cite"
cite=3D"mid:CAPTD5yHqydNOBA_GTtQRf8XLA-TLdocYAAhLSK-zXAPdgo+rpQ@mail.gmai=
l.com">
      <pre class=3D"moz-quote-pre" wrap=3D"">
Kind regards,
Jorg

</pre>
    </blockquote>
  </body>
</html>

--------------ua81tOZZCoOqu18mdhnMoo4a--
--------------oiintvTFZ3ryqlelIV0Lx4Vh
Content-Type: application/pgp-keys; name="OpenPGP_0x3936ABF753BC88CE.asc"
Content-Disposition: attachment; filename="OpenPGP_0x3936ABF753BC88CE.asc"
Content-Description: OpenPGP public key
Content-Transfer-Encoding: quoted-printable

-----BEGIN PGP PUBLIC KEY BLOCK-----
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3D
=3Doi2m
-----END PGP PUBLIC KEY BLOCK-----

--------------oiintvTFZ3ryqlelIV0Lx4Vh--

--------------1j7EtL1Pckv32xDx0X4in3ig--

--------------mKqM74x7iLKM3nHRupxXGOUL
Content-Type: application/pgp-signature; name="OpenPGP_signature.asc"
Content-Description: OpenPGP digital signature
Content-Disposition: attachment; filename="OpenPGP_signature.asc"

-----BEGIN PGP SIGNATURE-----

wsB5BAABCAAjFiEENJIbKB0SAX2RmUKbOTar91O8iM4FAmXbMakFAwAAAAAACgkQOTar91O8iM49
UwgAt1WWr2H5XV+Q9ObtTyjfvbiDEOR0npugqBlmP0wPusfds7t1tI2DDh0snV4jEnRklNwqMKKz
8C04NP1DBTruh5dMDbgmxrc7urEkVlbNBgKLEtThSioRzAOYh4p9tEuUbPNDlyHExu3emWmYhh6E
E4xboo8ejKXDao/JbRN0uybPlxHhZNosZJnlXOVLzFoo5bAE0Hxfo1upc3Qs0c7lGxr+fhAIwHwW
/YMeW49c6CN/juskNwuuLXYi2Ck4C+XIg9QB1dtn6UsCDkDoNhkREGgDMZA4HTnjtNiRVgQWGhIa
DIK6EU+MUPIZjHhQ0Ko7SREZr0qiLnzcf8qP1/jbTA==
=2tZT
-----END PGP SIGNATURE-----

--------------mKqM74x7iLKM3nHRupxXGOUL--