computePatternLValues() — react Function Reference

Source Code

compiler/packages/babel-plugin-react-compiler/src/ReactiveScopes/PruneNonEscapingScopes.ts lines 354–391

function computePatternLValues(pattern: Pattern): Array<LValueMemoization> {
  const lvalues: Array<LValueMemoization> = [];
  switch (pattern.kind) {
    case 'ArrayPattern': {
      for (const item of pattern.items) {
        if (item.kind === 'Identifier') {
          lvalues.push({place: item, level: MemoizationLevel.Conditional});
        } else if (item.kind === 'Spread') {
          lvalues.push({place: item.place, level: MemoizationLevel.Memoized});
        }
      }
      break;
    }
    case 'ObjectPattern': {
      for (const property of pattern.properties) {
        if (property.kind === 'ObjectProperty') {
          lvalues.push({
            place: property.place,
            level: MemoizationLevel.Conditional,
          });
        } else {
          lvalues.push({
            place: property.place,
            level: MemoizationLevel.Memoized,
          });
        }
      }
      break;
    }
    default: {
      assertExhaustive(
        pattern,
        `Unexpected pattern kind \`${(pattern as any).kind}\``,
      );
    }
  }
  return lvalues;
}