Function for_each_measure_in_block 

pub fn for_each_measure_in_block<Predicate>(
    blob_storage: Arc<BlobStorage>,
    convert_ticks: &ConvertTicks,
    process: Arc<ProcessMetadata>,
    stream: &StreamMetadata,
    block: &BlockMetadata,
    fun: Predicate,
) -> impl Future<Output = Result<bool, Error>>
where
    Predicate: FnMut(Measure) -> Result<bool, Error>,

Iterates over each metric measurement in a block.