lib/index.js
function updateIn(record, accessor, updator, ctx) {
    if (!updator) {
        return record;
    }
    return mutate(record, accessor, MutateType.updateIn, updator, ctx);
}
function updateIn(record, accessor, updator, ctx) {
    if (!updator) {
        return record;
    }
    return mutate(record, accessor, MutateType.updateIn, updator, ctx);
}
function updateIn ( record , accessor , updator , ctx ) { if ( ! updator ) { return record ; } return mutate ( record , accessor , MutateType . updateIn , updator , ctx ) ; }
Update a deep child by old value
@param record The object to update, it can be a plain object or a class instance
@param accessor A lambda function to get the key path, support dot, [''], [""], [1], **do not** support dynamic variable, function call, e.g.
@param updator A update function that take the old value and return the new value.
@param ctx Dynamic key map.
Update a deep child by old value