implement correct ranges for level-*
var ltgt = require('ltgt')
ltgt.start(range) //the start of the range
ltgt.end(range) //the end of the range
//returns the lower/upper bound, whether it's inclusive or not.
ltgt.lowerBound(range)
ltgt.upperBound(range)
ltgt.lt(range)
ltgt.gt(range)
ltgt.lte(range)
ltgt.gte(range)
//return wether this is a reversed order
//(this is significant for start/end ranges
ltgt.reverse(range)
var filter = ltgt.filter(range)
filter(key) == true //if key contained in range.
ltgt.contains(range, key)there have been a variety of ways to specify ranges in level-*. this module supports them all.
specify a range between a lower bound (gt, gte) and an upper bound (lt, lte)
if gte and gt is undefined, read from the start of the database,
if lte and lt is undefined, read until the end of the database,
legacy level-sublevel style,
synonym for gte, lte.
legacy levelup style.
The range is from start -> end, start does not specify the lowest
record, instead it specifies the first record to be read. However,
reverse must also be passed correctly. This is way to specify a range is
confusing if you need to read in reverse,
so it's strongly recommended to use gt/gte,lt/lte.
If reverse is true,
start must be undefined or less than end,
unless end is undefined.
if reverse is false
end must be undefined or greater than start,
unless start is undefined.
if start is undefined, read from the first record in the database if end is undefined read until the last record in the database.
using the provided compare method, return true if key
is within range. compare defaults to ltgt.compare
return a function that returns true if it's argument is within range.
can be passed to Array.filter
[1,2,3,4,5].filter(ltgt.filter({gt: 2, lte: 4})
// => [3, 4]