Class LangiumParser

Base interface for all parsers. Mainly used by the parser-builder-base.ts to perform work on different kinds of parsers. The main use cases are:

AST parser: Based on a string, create an AST for the current grammar
Completion parser: Based on a partial string, identify the current position of the input within the grammar

Hierarchy (view full)

AbstractLangiumParser
- LangiumParser

Index

Constructors

constructor

new LangiumParser(services): LangiumParser
Parameters
- services: LangiumCoreServices
Returns LangiumParser
Overrides AbstractLangiumParser.constructor
- Defined in packages/langium/src/parser/langium-parser.ts:205

Properties

`Protected`_unorderedGroups

_unorderedGroups: Map<string, boolean[]> = ...

`Protected`allRules

allRules: Map<string, RuleResult> = ...

`Protected` `Readonly`lexer

lexer: Lexer

`Protected`mainRule

mainRule: RuleResult

`Protected` `Readonly`wrapper

wrapper: ChevrotainWrapper

Accessors

definitionErrors

get definitionErrors(): IParserDefinitionError[]
Returns IParserDefinitionError[]
- Defined in packages/langium/src/parser/langium-parser.ts:433

unorderedGroups

get unorderedGroups(): Map<string, boolean[]>
Current state of the unordered groups

Returns Map<string, boolean[]>
Inherited from AbstractLangiumParser.unorderedGroups
- Defined in packages/langium/src/parser/langium-parser.ts:176

Methods

action

action($type, action): void
Executes a grammar action that modifies the currently active AST node
Parameters
- $type: string
- action: GrammarAST.Action
Returns void
Overrides AbstractLangiumParser.action
- Defined in packages/langium/src/parser/langium-parser.ts:340

alternatives

alternatives(idx, choices): void
Performs alternatives parsing (the | operation in EBNF/Langium)
Parameters
- idx: number
- choices: IOrAlt<any>[]
Returns void
Inherited from AbstractLangiumParser.alternatives
- Defined in packages/langium/src/parser/langium-parser.ts:146

atLeastOne

atLeastOne(idx, callback): void
Parses the callback 1 or more times (the + operation in EBNF/Langium)
Parameters
- idx: number
- callback: DSLMethodOpts<unknown>
Returns void
Inherited from AbstractLangiumParser.atLeastOne
- Defined in packages/langium/src/parser/langium-parser.ts:158

construct

construct(): unknown
Finishes construction of the current AST node. Only used by the AST parser.

Returns unknown
Overrides AbstractLangiumParser.construct
- Defined in packages/langium/src/parser/langium-parser.ts:357

consume

consume(idx, tokenType, feature): void
Consumes a specific token type from the token input stream. Requires a unique index within the rule for a specific token type.
Parameters
- idx: number
- tokenType: TokenType
- feature: GrammarAST.AbstractElement
Returns void
Overrides AbstractLangiumParser.consume
- Defined in packages/langium/src/parser/langium-parser.ts:274

finalize

finalize(): void
Returns void
Inherited from AbstractLangiumParser.finalize
- Defined in packages/langium/src/parser/langium-parser.ts:184

getRule

getRule(name): undefined | RuleResult
Returns the executable rule function for the specified rule name
Parameters
- name: string
Returns undefined | RuleResult
Inherited from AbstractLangiumParser.getRule
- Defined in packages/langium/src/parser/langium-parser.ts:168

getRuleStack

getRuleStack(): number[]
The rule stack indicates the indices of rules that are currently invoked, in order of their invocation.

Returns number[]
Inherited from AbstractLangiumParser.getRuleStack
- Defined in packages/langium/src/parser/langium-parser.ts:180

isRecording

isRecording(): boolean
Whether the parser is currently actually in use or in "recording mode". Recording mode is activated once when the parser is analyzing itself. During this phase, no input exists and therefore no AST should be constructed

Returns boolean
Inherited from AbstractLangiumParser.isRecording
- Defined in packages/langium/src/parser/langium-parser.ts:172

many

many(idx, callback): void
Parses the callback 0 or more times (the * operation in EBNF/Langium)
Parameters
- idx: number
- callback: DSLMethodOpts<unknown>
Returns void
Inherited from AbstractLangiumParser.many
- Defined in packages/langium/src/parser/langium-parser.ts:154

optional

optional(idx, callback): void
Parses the callback as optional (the ? operation in EBNF/Langium)
Parameters
- idx: number
- callback: DSLMethodOpts<unknown>
Returns void
Inherited from AbstractLangiumParser.optional
- Defined in packages/langium/src/parser/langium-parser.ts:150

parse

parse<T>(input, options?): ParseResult<T>
Type Parameters
- T extends AstNode = AstNode
Parameters
- input: string
- options: ParserOptions = {}
Returns ParseResult<T>
- Defined in packages/langium/src/parser/langium-parser.ts:233

rule

rule(rule, impl): RuleResult
Adds a new parser rule to the parser
Parameters
- rule: GrammarAST.ParserRule
- impl: RuleImpl
Returns RuleResult
Overrides AbstractLangiumParser.rule
- Defined in packages/langium/src/parser/langium-parser.ts:212

subrule

subrule(idx, rule, feature, args): void
Invokes the executable function for a given parser rule. Requires a unique index within the rule for a specific sub rule. Arguments can be supplied to the rule invocation for semantic predicates
Parameters
- idx: number
- rule: RuleResult
- feature: GrammarAST.AbstractElement
- args: Args
Returns void
Overrides AbstractLangiumParser.subrule
- Defined in packages/langium/src/parser/langium-parser.ts:303

Class LangiumParser

Hierarchy (view full)

Index

Constructors

Properties

Accessors

Methods

Constructors

constructor

Parameters

Returns LangiumParser

Properties

Protected_unorderedGroups

ProtectedallRules

Protected Readonlylexer

ProtectedmainRule

Protected Readonlywrapper

Accessors

definitionErrors

Returns IParserDefinitionError[]

unorderedGroups

Returns Map<string, boolean[]>

Methods

action

Parameters

Returns void

alternatives

Parameters

Returns void

atLeastOne

Parameters

Returns void

construct

Returns unknown

consume

Parameters

Returns void

finalize

Returns void

getRule

Parameters

Returns undefined | RuleResult

getRuleStack

Returns number[]

isRecording

Returns boolean

many

Parameters

Returns void

optional

Parameters

Returns void

parse

Type Parameters

Parameters

Returns ParseResult<T>

rule

Parameters

Returns RuleResult

subrule

Parameters

Returns void

Settings

On This Page

`Protected`_unorderedGroups

`Protected`allRules

`Protected` `Readonly`lexer

`Protected`mainRule

`Protected` `Readonly`wrapper