import {AutoReplacer} from 'projectq/src/cengines/replacer/replacer.js'

public class | source

AutoReplacer

Extends:

BasicEngine → AutoReplacer

The AutoReplacer is a compiler engine which uses engine.isAvailable in order to determine which commands need to be replaced/decomposed/compiled further. The loaded setup is used to find decomposition rules appropriate for each command (e.g., setups.default).

Constructor Summary

Public Constructor
public	constructor(decompositionRuleSet: DecompositionRuleSet, decomposition_chooser: function)

Member Summary

Public Members
public	decompositionRuleSet: *

Private Members
private	_decomp_chooser: *

Method Summary

Public Methods
public	receive(commandList: *)

Private Methods
private	_processCommand(cmd: Command) Check whether a command cmd can be handled by further engines and, if not, replace it using the decomposition rules loaded with the setup (e.g., setups.default).

Inherited Summary

From class BasicEngine
public	isLastEngine: boolean
public	allocateQubit(dirty: boolean): Qureg Return a new qubit as a list containing 1 qubit object (quantum register of size 1).
public	allocateQureg(n: number): Qureg Allocate n qubits and return them as a quantum register, which is a list of qubit objects.
public	deallocateQubit(qubit: BasicQubit) Deallocate a qubit (and sends the deallocation command down the pipeline).
public	isAvailable(cmd: Command): boolean Default implementation of isAvailable: Ask the next engine whether a command is available, i.e., whether it can be executed by the next engine(s).
public	isMetaTagSupported(metaTag: function): boolean Check if there is a compiler engine handling the meta tag
public	receive()
public	send(commandList: Command[]) Forward the list of commands to the next engine in the pipeline.

Public Constructors

public constructor(decompositionRuleSet: DecompositionRuleSet, decomposition_chooser: function) source

Override:

BasicEngine#constructor

Params:

Name	Type	Attribute	Description
decompositionRuleSet	DecompositionRuleSet
decomposition_chooser	function	nullable: true	A function which, given the Command to decompose and a list of potential Decomposition objects, determines (and then returns) the 'best' decomposition. The default decomposition chooser simply returns the first list element, i.e., calling

Name

Type

Attribute

Description

decompositionRuleSet

DecompositionRuleSet

decomposition_chooser

function

nullable: true

A function which, given the Command to decompose and a list of potential Decomposition objects, determines (and then returns) the 'best' decomposition.

The default decomposition chooser simply returns the first list element, i.e., calling

Example:


repl = new AutoReplacer()

Amounts to


function decomposition_chooser(cmd, decomp_list) {
return decomp_list[0]
}
const repl = new AutoReplacer(decomposition_chooser)

Public Members

public decompositionRuleSet: * source

Private Members

private _decomp_chooser: * source

Public Methods

public receive(commandList: *) source

Override:

BasicEngine#receive

Params:

Name	Type	Attribute	Description
commandList	*

Private Methods

private _processCommand(cmd: Command) source

Check whether a command cmd can be handled by further engines and, if not, replace it using the decomposition rules loaded with the setup (e.g., setups.default).

Params:

Name	Type	Attribute	Description
cmd	Command		Command to process.

Throw:

*	Exception if no replacement is available in the loaded setup.