Class default

OpenQASM 3.0 Recursive Descent Parser

Implements a comprehensive parser for the OpenQASM 3.0 language specification. The parser uses recursive descent parsing with appropriate error recovery and maintains symbol tables for gates, subroutines, and variables.

Parser state includes:

Token stream and current position
Symbol tables for gates, subroutines, arrays, aliases
Machine-specific defaults (float width, int size)

Example: Creating and using the parser

const parser = new Parser(tokens);

// Parse the entire program
const ast = parser.parse();

// AST contains array of top-level statements and declarations
console.log(ast); // [VersionNode, IncludeNode, DeclarationNode, ...]

Index

Constructors

constructor

Properties

aliases customArrays customGates gates index machineFloatWidth machineIntSize standardGates subroutines tokens

Constructors

constructor

new default(
    tokens: [Token, (string | number)?][],
    defaultFloatWidth?: number,
    machineIntSize?: number,
): default
Creates a parser.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
- OptionaldefaultFloatWidth: number
  Optional default float width override.
- OptionalmachineIntSize: number
  Optional default int size override.
Returns default
- Defined in src/qasm3/parser.ts:217

Methods

aliasStatement

aliasStatement(tokens: [Token, (string | number)?][]): [AliasStatement, number]
Parses an alias statement.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [AliasStatement, number]
A tuple containing the AliasStatement and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:1791

arrayDeclaration

arrayDeclaration(
tokens: [Token, (string | number)?][],
): [ArrayDeclaration, number]
Parses an array statement.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [ArrayDeclaration, number]
An ArrayDeclaration node and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:2244

assignment

assignment(tokens: [Token, (string | number)?][]): [AssignmentStatement, number]
Parses an assignment statement.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [AssignmentStatement, number]
The parsed AssignmentStatement AstNode and the number of consumed tokens.
- Defined in src/qasm3/parser.ts:874

barrier

barrier(tokens: [Token, (string | number)?][]): [QuantumBarrier, number]
Parses a barrier statement.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [QuantumBarrier, number]
An QuantumBarrier node and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:2195

binaryExpression

binaryExpression(tokens: [Token, (string | number)?][]): [Expression, number]
Parses a binary expression.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [Expression, number]
A tuple containing the parsed Expression and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:829

box

box(tokens: [Token, (string | number)?][]): [BoxDefinition, number]
Parses a box statement.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [BoxDefinition, number]
An BoxDefinition node and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:2211

classicalDeclaration

classicalDeclaration(
tokens: [Token, (string | number)?][],
isConst?: boolean,
): [ClassicalDeclaration, number]
Parses a classical type declaration.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
- OptionalisConst: boolean
  Whether the declaration is for a constant, defaults to False.
Returns [ClassicalDeclaration, number]
The parsed ClassicalDeclaration AstNode and the number of consumed tokens.
- Defined in src/qasm3/parser.ts:598

createClassicalType

createClassicalType(token: Token, width?: number | Expression): ClassicalType
Creates a classical type.
Parameters
- token: Token
  The token that represents the type.
- Optionalwidth: number | Expression
  The type's width or size, if applicable.
Returns ClassicalType
The created ClassicalType.
- Defined in src/qasm3/parser.ts:2996

createMathOrTrigFunction

createMathOrTrigFunction(
token: Token,
expr: Expression,
): [MathFunction | TrigFunction, number]
Creates a math or trigonometric function node.
Parameters
- token: Token
  The token representing the function.
- expr: Expression
  The expression to which the function is applied.
Returns [MathFunction | TrigFunction, number]
The created MathFunction or TrigFunction node and the number of consumed tokens.
- Defined in src/qasm3/parser.ts:3035

defcalGrammarDeclaration

defcalGrammarDeclaration(
tokens: [Token, (string | number)?][],
): [CalibrationGrammarDeclaration, number]
Parses a defcalgrammar declaration.

calibrationGrammarStatement: DEFCALGRAMMAR StringLiteral SEMICOLON
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [CalibrationGrammarDeclaration, number]
The parsed CalibrationGrammarDeclaration AstNode node and the number of consumed tokens.
- Defined in src/qasm3/parser.ts:572

delay

delay(tokens: [Token, (string | number)?][]): [QuantumDelay, number]
Parses a delay statement.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [QuantumDelay, number]
A QuantumDelay node and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:2616

durationOf

durationOf(tokens: [Token, (string | number)?][]): [DurationOf, number]
Parses a durationof function call.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [DurationOf, number]
A DurationOf node and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:2666

externSignature

externSignature(
tokens: [Token, (string | number)?][],
): [ExternSignature, number]
Parses an extern signature.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [ExternSignature, number]
A tuple containing the ExternSignature and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:1226

forLoopStatement

forLoopStatement(
tokens: [Token, (string | number)?][],
): [ForLoopStatement, number]
Parses a for loop.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [ForLoopStatement, number]
A ForLoopStatement node and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:2091

ifStatement

ifStatement(tokens: [Token, (string | number)?][]): [BranchingStatement, number]
Parses a branching condition (if) statement.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [BranchingStatement, number]
A BranchingStatement node representing the if statement and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:2039

include

include(tokens: [Token, (string | number)?][]): [Include, number]
Parses an include statement.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [Include, number]
An Include node representing the include statement and the number of consumed tokens.
- Defined in src/qasm3/parser.ts:2813

ioType

ioType(tokens: [Token, (string | number)?][]): [IODeclaration, number]
Parses an IO declaration statement.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [IODeclaration, number]
A tuple containing the parsed IODeclaration and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:646

matchNext

matchNext(
tokens: [Token, (string | number)?][],
expectedTokens: Token[],
): boolean
Checks if the next tokens match those expected.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
- expectedTokens: Token[]
  Expected tokens.
Returns boolean
Whether these is a match.
- Defined in src/qasm3/parser.ts:544

measureStatement

measureStatement(
tokens: [Token, (string | number)?][],
): [QuantumMeasurement | QuantumMeasurementAssignment, number]
Parses a measure statement.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [QuantumMeasurement | QuantumMeasurementAssignment, number]
A tuple containing the QuantumMeasurementAssignment or QuantumMeasurement and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:1067

parse

parse(): AstNode[]
Parses the token stream and generates an abstract syntax tree.

Returns AstNode[]
The abstract syntax tree.
- Defined in src/qasm3/parser.ts:280

parseArrayAccess

parseArrayAccess(tokens: [Token, (string | number)?][]): [ArrayAccess, number]
Parses an array access.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [ArrayAccess, number]
An ArrayAccess node and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:2386

parseArrayInitializer

parseArrayInitializer(
tokens: [Token, (string | number)?][],
): [Expression | ArrayInitializer, number]
Parses an array initializer.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [Expression | ArrayInitializer, number]
An ArrayInitializer node and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:2336

parseArrayReference

parseArrayReference(
tokens: [Token, (string | number)?][],
): [ArrayReference, number]
Parses an array reference.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [ArrayReference, number]
A tuple containing the ArrayReference and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:1756

parseCaseStatement

parseCaseStatement(
tokens: [Token, (string | number)?][],
): [CaseStatement, number]
Parses a case statement.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [CaseStatement, number]
A CaseStatement node and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:2555

parseClassicalType

parseClassicalType(
tokens: [Token, (string | number)?][],
): [ClassicalType, number]
Parses a classical type.
Parameters
- tokens: [Token, (string | number)?][]
Returns [ClassicalType, number]
The ClassicalType and the number of consumed tokens.
- Defined in src/qasm3/parser.ts:2881

parseDefaultStatement

parseDefaultStatement(
tokens: [Token, (string | number)?][],
): [DefaultStatement, number]
Parses a default statement.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [DefaultStatement, number]
A DefaultStatement node and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:2591

parseHardwareQubit

parseHardwareQubit(
tokens: [Token, (string | number)?][],
): [HardwareQubit, number]
Parses a hardware qubit.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [HardwareQubit, number]
A tuple containing the HardwareQubit and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:1593

parseIndexSet

parseIndexSet(tokens: [Token, (string | number)?][]): [IndexSet, number]
Parses an index set.
Parameters
- tokens: [Token, (string | number)?][]
Returns [IndexSet, number]
The resulting Identifier, IndexSet, or Range node and the number of consumed tokens.
- Defined in src/qasm3/parser.ts:2961

parseNode

parseNode(
tokens: [Token, (string | number)?][],
allowVariables?: boolean,
): [AstNode[], number]
Parses a single statement or declaration by delegating the parsing of the next set of tokens to the appropriate method.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
- allowVariables: boolean = true
  Whether encountered identifiers should be consider variable initializations or references.
Returns [AstNode[], number]
A set of AST nodes and the number of consumed tokens.
- Defined in src/qasm3/parser.ts:316

parseParameters

parseParameters(tokens: [Token, (string | number)?][]): [Parameters, number]
Parses a set of parameters.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [Parameters, number]
A tuple containing the Parameters and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:1687

parseQuantumGateModifier

parseQuantumGateModifier(
tokens: [Token, (string | number)?][],
): [QuantumGateModifier, number]
Parses a gate modifier.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [QuantumGateModifier, number]
A tuple containing the gate modifier and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:1622

parseQubitList

parseQubitList(
tokens: [Token, (string | number)?][],
): [(Identifier | SubscriptedIdentifier | HardwareQubit)[], number]
Parses a list of qubits.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [(Identifier | SubscriptedIdentifier | HardwareQubit)[], number]
A tuple containing the list of qubits and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:1544

parseSetDeclaration

parseSetDeclaration(
tokens: [Token, (string | number)?][],
): [Expression | Range | IndexSet, number]
Parses a set declaration.
Parameters
- tokens: [Token, (string | number)?][]
Returns [Expression | Range | IndexSet, number]
The resulting Identifier, IndexSet, or Range node and the number of consumed tokens.
- Defined in src/qasm3/parser.ts:2941

parseSubscript

parseSubscript(
tokens: [Token, (string | number)?][],
): [Expression | Range | IndexSet, number]
Parses a subscript expression as a Range.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [Expression | Range | IndexSet, number]
A tuple containing the parsed Expression or Range and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:1877

parseTypeCast

parseTypeCast(tokens: [Token, (string | number)?][]): [Expression, number]
Parses a type cast expression.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [Expression, number]
A tuple containing the parsed Cast Expression and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:1985

programBlock

programBlock(tokens: [Token, (string | number)?][]): [ProgramBlock, number]
Parses a program block.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [ProgramBlock, number]
A ProgramBlock node and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:2755

quantumDeclaration

quantumDeclaration(
tokens: [Token, (string | number)?][],
): [QuantumDeclaration, number]
Parses a quantum declaration.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [QuantumDeclaration, number]
A QuantumDeclaration node and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:977

quantumGateCall

quantumGateCall(
tokens: [Token, (string | number)?][],
): [QuantumGateCall, number]
Parses a quantum gate call.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [QuantumGateCall, number]
A tuple containing the QuantumGateCall and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:1468

quantumGateDefinition

quantumGateDefinition(
tokens: [Token, (string | number)?][],
): [QuantumGateDefinition, number]
Parses a quantum gate definition.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [QuantumGateDefinition, number]
A tuple containing the QuantumGateDefinition and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:1398

resetStatement

resetStatement(tokens: [Token, (string | number)?][]): [QuantumReset, number]
Parses a quantum reset.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [QuantumReset, number]
A tuple containing the QuantumReset and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:1845

returnStatement

returnStatement(
tokens: [Token, (string | number)?][],
): [ReturnStatement, number]
Parses a subroutine return statement.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [ReturnStatement, number]
A tuple containing the SubroutineDefinition and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:1206

sizeOf

sizeOf(tokens: [Token, (string | number)?][]): [SizeOf, number]
Parses a sizeof function call.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [SizeOf, number]
A SizeOf node and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:2712

stdGates

stdGates(): void
Loads the standard library gates.

Returns void
- Defined in src/qasm3/parser.ts:237

subroutineCall

subroutineCall(tokens: [Token, (string | number)?][]): [SubroutineCall, number]
Parses a subroutine call.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [SubroutineCall, number]
A tuple containing the SubroutineCall and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:1349

subroutineDefinition

subroutineDefinition(
tokens: [Token, (string | number)?][],
): [SubroutineDefinition, number]
Parses a subroutine definition.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [SubroutineDefinition, number]
A tuple containing the SubroutineDefinition and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:1283

switchStatement

switchStatement(
tokens: [Token, (string | number)?][],
): [SwitchStatement, number]
Parses a switch statement.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [SwitchStatement, number]
A SwitchStatement node and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:2463

unaryExpression

unaryExpression(tokens: [Token, (string | number)?][]): [Expression, number]
Parses a unary expression.
Parameters
- tokens: [Token, (string | number)?][]
  Remaining tokens to parse.
Returns [Expression, number]
A tuple containing the parsed Expression and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:677

versionHeader

versionHeader(tokens: [Token, (string | number)?][]): [Version, number]
Parses the version header and sets the parser version.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [Version, number]
A Version node representing the version statement and the number of consumed tokens.
- Defined in src/qasm3/parser.ts:2835

whileLoopStatement

whileLoopStatement(
tokens: [Token, (string | number)?][],
): [WhileLoopStatement, number]
Parses a while loop.
Parameters
- tokens: [Token, (string | number)?][]
  Tokens to parse.
Returns [WhileLoopStatement, number]
A ForLoopStatement node and the number of tokens consumed.
- Defined in src/qasm3/parser.ts:2154

Properties

aliases

aliases: Map<string, string>

User defined aliases.

customArrays

customArrays: Set<string>

User defined arrays.

customGates

customGates: Set<string>

Custom defined gates.

gates

gates: Set<string>

The built in gates.

index

index: number

Index of the current token.

machineFloatWidth

machineFloatWidth: number

The default machine precision float width.

machineIntSize

machineIntSize: number

The default machine int size.

standardGates

standardGates: Set<string>

Standard library gates.

subroutines

subroutines: Set<string>

Custom defined subroutines.

tokens

tokens: [Token, (string | number)?][]

The tokens to parse.

Class default

Example: Creating and using the parser

Index

Constructors

Methods

Properties

Constructors

constructor

Parameters

Returns default

Methods

aliasStatement

Parameters

Returns [AliasStatement, number]

arrayDeclaration

Parameters

Returns [ArrayDeclaration, number]

assignment

Parameters

Returns [AssignmentStatement, number]

barrier

Parameters

Returns [QuantumBarrier, number]

binaryExpression

Parameters

Returns [Expression, number]

box

Parameters

Returns [BoxDefinition, number]

classicalDeclaration

Parameters

Returns [ClassicalDeclaration, number]

createClassicalType

Parameters

Returns ClassicalType

createMathOrTrigFunction

Parameters

Returns [MathFunction | TrigFunction, number]

defcalGrammarDeclaration

Parameters

Returns [CalibrationGrammarDeclaration, number]

delay

Parameters

Returns [QuantumDelay, number]

durationOf

Parameters

Returns [DurationOf, number]

externSignature

Parameters

Returns [ExternSignature, number]

forLoopStatement

Parameters

Returns [ForLoopStatement, number]

ifStatement

Parameters

Returns [BranchingStatement, number]

include

Parameters

Returns [Include, number]

ioType

Parameters

Returns [IODeclaration, number]

matchNext

Parameters

Returns boolean

measureStatement

Parameters

Returns [QuantumMeasurement | QuantumMeasurementAssignment, number]

parse

Returns AstNode[]

parseArrayAccess

Parameters

Returns [ArrayAccess, number]

parseArrayInitializer

Parameters

Returns [Expression | ArrayInitializer, number]

parseArrayReference

Parameters

Returns [ArrayReference, number]

parseCaseStatement