function contStart(code) {
    if (markdownSpace(code)) {
      // Always populated by defaults.
      assert(
        self.parser.constructs.disable.null,
        'expected `disable.null` to be populated'
      )

      return factorySpace(
        effects,
        contBefore,
        types.linePrefix,
        self.parser.constructs.disable.null.includes('codeIndented')
          ? undefined
          : constants.tabSize
      )(code)
    }

    return contBefore(code)
  }
Start of block quote continuation.

Also used to parse the first block quote opening.

```markdown
  | > a
> | > b
    ^
```

@type {State}