packages/postcss-merge-rules/src/index.js
function intersect(a, b, not) {
  return a.filter((c) => {
    const index = ~indexOfDeclaration(b, c);
    return not ? !index : index;
  });
}
function intersect(a, b, not) {
  return a.filter((c) => {
    const index = ~indexOfDeclaration(b, c);
    return not ? !index : index;
  });
}
function intersect ( a , b , not ) { return a . filter ( ( c ) => { const index = ~ indexOfDeclaration ( b , c ) ; return not ? ! index : index ; } ) ; }
Returns filtered array of matched or unmatched declarations
@param {postcss.Declaration[]} a
@param {postcss.Declaration[]} b
@param {boolean} [not=false]
@return {postcss.Declaration[]}
Returns filtered array of matched or unmatched declarations