lib/TreeSearch.js
// A helper function for performing a tree search with a function
A helper function for performing a tree search with a function
A helper function for performing a tree search with a function
function search(simplificationFunction, node, preOrder) {
  let status;
  if (preOrder) {
    status = simplificationFunction(node);
    if (status.hasChanged()) {
      return status;
    }
  }
  if (Node.Type.isConstant(node) || Node.Type.isSymbol(node)) {
    return Node.Status.noChange(node);
  }
  else if (Node.Type.isUnaryMinus(node)) {
    status = search(simplificationFunction, node.args[0], preOrder);
    if (status.hasChanged()) {
      return Node.Status.childChanged(node, status);
    }
  }
  else if (Node.Type.isOperator(node) || Node.Type.isFunction(node)) {
    for (let i = 0; i < node.args.length; i++) {
      const child = node.args[i];
      const childNodeStatus = search(simplificationFunction, child, preOrder);
      if (childNodeStatus.hasChanged()) {
        return  Node.Status.childChanged(node, childNodeStatus, i);
      }
    }
  }
  else if (Node.Type.isParenthesis(node)) {
    status = search(simplificationFunction, node.content, preOrder);
    if (status.hasChanged()) {
      return Node.Status.childChanged(node, status);
    }
  }
  else {
    throw Error('Unsupported node type: ' + node);
  }
  if (!preOrder) {
    return simplificationFunction(node);
  }
  else {
    return Node.Status.noChange(node);
  }
}
function search ( simplificationFunction , node , preOrder ) { let status ; if ( preOrder ) { status = simplificationFunction ( node ) ; if ( status . hasChanged ( ) ) { return status ; } } if ( Node . Type . isConstant ( node ) || Node . Type . isSymbol ( node ) ) { return Node . Status . noChange ( node ) ; } else if ( Node . Type . isUnaryMinus ( node ) ) { status = search ( simplificationFunction , node . args [ 0 ] , preOrder ) ; if ( status . hasChanged ( ) ) { return Node . Status . childChanged ( node , status ) ; } } else if ( Node . Type . isOperator ( node ) || Node . Type . isFunction ( node ) ) { for ( let i = 0 ; i < node . args . length ; i ++ ) { const child = node . args [ i ] ; const childNodeStatus = search ( simplificationFunction , child , preOrder ) ; if ( childNodeStatus . hasChanged ( ) ) { return Node . Status . childChanged ( node , childNodeStatus , i ) ; } } } else if ( Node . Type . isParenthesis ( node ) ) { status = search ( simplificationFunction , node . content , preOrder ) ; if ( status . hasChanged ( ) ) { return Node . Status . childChanged ( node , status ) ; } } else { throw Error ( 'Unsupported node type: ' + node ) ; } if ( ! preOrder ) { return simplificationFunction ( node ) ; } else { return Node . Status . noChange ( node ) ; } }
A helper function for performing a tree search with a function
A helper function for performing a tree search with a function