function factory
returns a function that checks if a bedgraph line overlaps a given interval. along with UCSC convention, end coordinate is open and start coordinate is 0-based (also compatible with BED files)
function factory
returns a function that checks if a bedgraph line overlaps any given interval. assumes we already filtered by chrom
intervals must be given as tuples (int start, int end)
along with UCSC convention, end coordinate is open and start coordinate is 0-based (also compatible with BED files)