Function parseConnectedBlocks

packages/compiler/src/render3/r3_deferred_blocks.ts:106–165

(
  connectedBlocks: html.Block[],
  errors: ParseError[],
  visitor: html.Visitor,
)

}

function parseConnectedBlocks(
  connectedBlocks: html.Block[],
  errors: ParseError[],
  visitor: html.Visitor,
) {
  let placeholder: t.DeferredBlockPlaceholder | null = null;
  let loading: t.DeferredBlockLoading | null = null;
  let error: t.DeferredBlockError | null = null;

  for (const block of connectedBlocks) {
    try {
      if (!isConnectedDeferLoopBlock(block.name)) {
        errors.push(new ParseError(block.startSourceSpan, `Unrecognized block "@${block.name}"`));
        break;
      }

      switch (block.name) {
        case 'placeholder':
          if (placeholder !== null) {
            errors.push(
              new ParseError(
                block.startSourceSpan,
                `@defer block can only have one @placeholder block`,
              ),
            );
          } else {
            placeholder = parsePlaceholderBlock(block, visitor);
          }
          break;

        case 'loading':
          if (loading !== null) {
            errors.push(
              new ParseError(
                block.startSourceSpan,
                `@defer block can only have one @loading block`,
              ),
            );
          } else {
            loading = parseLoadingBlock(block, visitor);
          }
          break;

        case 'error':
          if (error !== null) {
            errors.push(
              new ParseError(block.startSourceSpan, `@defer block can only have one @error block`),
            );
          } else {
            error = parseErrorBlock(block, visitor);
          }
          break;
      }
    } catch (e) {
      errors.push(new ParseError(block.startSourceSpan, (e as Error).message));
    }
  }