Function convertForeachClause

packages/graph/src/astToSteps.ts:1066–1114

* Convert a FOREACH clause into a ForeachStep.

(foreachClause: ForeachClause)

 * Convert a FOREACH clause into a ForeachStep.
 */
function convertForeachClause(foreachClause: ForeachClause): ForeachStep<Step<any>[]> {
  const { variable, listExpression, operations } = foreachClause;

  // Convert the list expression
  const stepListExpression = convertListExpression(listExpression);

  // Convert the operations to inner steps
  const innerSteps: Step<any>[] = [];
  for (const operation of operations) {
    if (operation.type === "SetOperation") {
      const setOp = operation as ASTSetOperation;
      const setStep = convertSetOperationToStep(setOp);
      innerSteps.push(setStep);
    } else if (operation.type === "DeleteOperation") {
      // Convert DELETE/DETACH DELETE operations inside FOREACH
      const deleteOp = operation as ASTDeleteOperation;
      const deleteStep = new DeleteStep({
        variables: deleteOp.variables,
        detach: deleteOp.detach,
      });
      innerSteps.push(deleteStep);
    } else if (operation.type === "MatchClause") {
      // Convert MATCH operations inside FOREACH
      const matchClause = operation as MatchClause;
      const matchPattern = matchClause.pattern;

      if (matchPattern.type === "ShortestPathPattern") {
        // Convert shortestPath pattern to steps
        const shortestPathSteps = convertShortestPathPattern(
          matchPattern as ShortestPathPattern,
          matchClause.where,
        );
        innerSteps.push(...shortestPathSteps);
      } else {
        // Regular pattern - convert to steps
        const matchSteps = convertPattern(matchPattern as Pattern, matchClause.where);
        innerSteps.push(...matchSteps);
      }
    }
  }

  return new ForeachStep(
    {
      variable,
      listExpression: stepListExpression,
    },
    innerSteps,
  );
}

/**
 * Convert a ListExpression AST node to a ForeachListExpression.