Function extractFromClauseGraphUris

extractFromClauseGraphUris(query?: string): string[]
Extracts the graph IRIs declared in FROM and FROM NAMED dataset clauses of a SPARQL query by walking the token stream produced by SparqlLexer.

Dataset clauses appear at the top of every SPARQL query form and satisfy the grammar productions:

DatasetClause ::= FROM ( DefaultGraphClause | NamedGraphClause ) DefaultGraphClause ::= SourceSelector NamedGraphClause ::= NAMED SourceSelector SourceSelector ::= iri

The function:
- Handles both FROM <iri> and FROM NAMED <iri> forms.
- Strips the surrounding angle brackets from IRIREF tokens.
- Deduplicates the returned list while preserving order of first occurrence.
- Returns an empty array for undefined / empty input or when no clauses exist.
Parameters
- Optionalquery: string
  The raw SPARQL query text.
Returns string[]
An ordered, deduplicated array of graph IRI strings.
- Defined in src/utils.ts:274