LanQ – a quantum imperative programming language

Declaration

{ block-forming statements }

Description

Groups given block-forming statements.

Declaration

fork methodName([p0 [, p1 [, ...]]]);

Description

Starts a new process. The process execution is started from given method methodName. Any nonduplicable resources passed as arguments to the newly started process become unavailable in the original process.

Declaration

if (expr) statement1 [else statement2]

Description

If given expr evaluates to true, executes the statement1, else executes the statement2.

Declaration

return;
return expr;

Description

Finishes execution of a method and eventually returns given expr as a return value of the method.

Declaration

send(channelEndName, value);

Description

Sends given value value over a channel whose one end is available to the process as channelEndName. Any nonduplicable resource passed as the sent value becomes unavailable in the sending process. This is a blocking operation.

Declaration

;

Description

Performs no operation.

Declaration

while (expr) statement

Description

While expr evaluates to true, executes given statement.

Declaration

channel[T] id0 withends [id1, id2];

Description

Declares a new channel variable id0 of type channel[T] and variables id1 and id2 of type channelEnd[T] which denote individual ends of the channel.

Declaration

id aliasfor [id0 [, id1 [, ...]]];

Description

Declares a new quantum variable id0 which acts as a compound quantum system whose components are quantum systems id1, id2, ...

Declaration

T id0 [, id1 [, ...]];

Description

Declares new variables id0, id1, ... of type T.

Declaration

new T()

Description

Allocates new quantum system (if T is a quantum type) or a new channel (if T is a channel type).

Return value

The newly allocated resource.

Declaration

x = expr

Description

Assigns the result of evaluation of given expr to variable x.

Return value

The result of evaluation of given expr.

Declaration

c

Description

Evaluates to the value of the constant c.

Return value

The value of the constant c.

Declaration

measure(basis, q0 [, q1 [, ...]])

Description

Measures given quantum systems q0, q1, ... in given measurement basis basis. Possible bases are StdBasis, DualBasis and BellBasis.

Return value

The index of the first eigenvalue which is returned as the measurement result.

Declaration

methodName([p0 [, p1 [, ...]]])

Description

Calls the method methodName with given arguments.

Return value

The return value of the called method.

Declaration

recv(channelEndName);

Description

Receives a value from given channel end. This is a blocking operation.

Return value

The received value.

Syntax

p0 != p1

Arguments

Name	Type	Description
p0	int	First number
p1	int	Second number

Description

Returns true iff the numbers are nonequal.

Syntax

p0 && p1

Arguments

Name	Type	Description
p0	bool	First operand
p1	bool	Second operand

Description

Returns true iff both operands are true.

Syntax

p0 || p1

Arguments

Name	Type	Description
p0	bool	First operand
p1	bool	Second operand

Description

Returns true iff either operand is true.

Syntax

p0 + p1

Arguments

Name	Type	Description
p0	int	First number
p1	int	Second number

Description

Adds two numbers and returns result.

Syntax

p0 - p1

Arguments

Name	Type	Description
p0	int	First number
p1	int	Second number

Description

Subtracts second number from the first and returns result.

Syntax

p0 * p1

Arguments

Name	Type	Description
p0	int	First number
p1	int	Second number

Description

Multiplies two numbers and returns result.

Syntax

p0 / p1

Arguments

Name	Type	Description
p0	int	Dividend
p1	int	Divisor

Description

Divides the first number by the second and returns the result.

Syntax

p0 % p1

Arguments

Name	Type	Description
p0	int	First number
p1	int	Second number

Description

Divides the first number by the second number and returns the remainder.

Syntax

p0 . p1

Arguments

Name	Type	Description
p0	string	First string
p1	string	Second string

or

Name	Type	Description
p0	string	First string
p1	int	Second integer

or

Name	Type	Description
p0	string	First integer
p1	int	Second string

Description

Concatenates the string representation of the arguments and returns the result string.

Syntax

p0 == p1

Arguments

Name	Type	Description
p0	int	First number
p1	int	Second number

Description

Returns true iff the numbers are equal.

Syntax

CNot( p0 , p1 )

Arguments

Name	Type	Description
p0	qbit	First qubit
p1	qbit	Second qubit

Description

Applies a CNOT operator to given qubits. Qubit p0 acts as a control qubit, qubit p1 acts as a target qubit.

Syntax

Had( p0 )

Arguments

Name	Type	Description
p0	qbit	Qubit to apply the operator on

Description

Applies Hadamard operator to given qubit.

Syntax

Sigma_x( p0 )

Arguments

Name	Type	Description
p0	qbit	Qubit to apply the operator on

Description

Applies Pauli sigma_x operator to given qubit.

Syntax

Sigma_y( p0 )

Arguments

Name	Type	Description
p0	qbit	Qubit to apply the operator on

Description

Applies Pauli sigma_y operator to given qubit.

Syntax

Sigma_z( p0 )

Arguments

Name	Type	Description
p0	qbit	Qubit to apply the operator on

Description

Applies Pauli sigma_z operator to given qubit.

Syntax

dump_q( p0 )

Arguments

Name	Type	Description
p0	q-0-it	Quantum system of any dimension

Description

Displays state (the density matrix) of given quantum system.

Syntax

print( p0 )

Arguments

Name	Type	Description
p0	int	Integer to print

or

Name	Type	Description
p0	string	String to print

Description

Prints given integer or string to standard output.