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RFC 225 (v2) Data: Superpositions

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September 18, 2000 18:05
RFC 225 (v2) Data: Superpositions
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=head1 TITLE

Data: Superpositions

=head1 VERSION

  Maintainer: Damian Conway <>
  Date: 14 Sep 2000
  Last Modified: 18 Sep 2000
  Mailing List:
  Number: 225
  Version: 2
  Status: Frozen


This RFC (seriously) proposes Perl 6 provide C<any> and C<all> operators,
and, thereby, conjunctive and disjunctive superpositional types.


The advantages and possibilities of superpositional programming were 
demonstrated in well-received presentations at both YAPC'19100 and TPC 4.0.

It is proposed that the C<any>, C<all>, and C<eigenstates> operators
proposed in those talks be added to Perl 6. Adding them to the core is
suggested because the use of superpositions changes the nature of
subroutine and operator invocations that have superpositions as
arguments. This is currently impossible to reproduce in a module.
Furthermore, the fundamental utility of being able to write:

        if (any(@value) < 10) { ... }


        die unless all(@tests)->($data);

ought to be available to all Perl users.

Inclusion in the core would also allow the current module-based pure Perl
implementation to be greatly optimized (perhaps even parallelized on suitable
SIMD or other multiprocessing platforms).

A paper proposing the full semantics of superpositions (including their
effect when used as subroutine arguments and operator operands) will soon
be available from:


The <any> and <all> functions may collide with existing user-defined
or module-exported subroutine names.


See the Quantum::Superpositions module.


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 [2] Einstein, A., †ber einen die Erzeugung und Verwandlung des Lichtes
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 [3] Lewis, G.N., The Conservation of Photons, Nature, v.118(2),
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 [4] Monroe, C., Meekhof, D.M., King, B.E., Itano, W.M. & Wineland, D.J.
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 [9] Cory, D.G., Fahmy, A.F. & Havel, T.F., Ensemble Quantum
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[10] Deutsch, D. Quantum Theory, the Church-Turing Principle and the
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[11] Deutsch, D. & Jozsa, R., Rapid Solution of Problems by Quantum
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[12] Shor, P. Algorithms for Quantum Computation: Discrete Logarithms
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[13] Grover, L.K., A Fast Quantum Mechanical Algorithm for Database
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[14] Wallace, J., Quantum Computer Simulators - A Review, Technical
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