Nesting from example not working with postcss

[Defite]

Latest version of typings-for-css-modules-loader, trying example:

.some-class {
  margin-left: 10px;

  &_modify {
    color: orange
  }
}

In typings I got:

export const someClass: string;

but there is no line like:

export const someClassModify: string;

In my component I use it like:

<SomeComponent className={styles.someClassModify}>

Is it supposed to work / not work this way?