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exports.add = add
exports.remove = remove
exports.has = has
exports.eq = eq
exports.lte = lte
exports.lt = lt
exports.gte = gte
exports.gt = gt
exports.nearest = nearest
function defaultCmp (a, b) {
if (a === b) return 0
return a > b ? 1 : -1
}
function add (list, value, cmp) {
if (!cmp) cmp = defaultCmp
var top = list.push(value) - 1
while (top) {
if (cmp(list[top - 1], value) < 0) return
list[top] = list[top - 1]
list[top - 1] = value
top--
}
}
function lte (list, value, cmp) {
if (!cmp) cmp = defaultCmp
var i = indexOf(list, value, cmp)
if (i === -1) return -1
for (; i >= 0; i--) {
var c = cmp(list[i], value)
if (c <= 0) return i
}
return -1
}
function lt (list, value, cmp) {
if (!cmp) cmp = defaultCmp
var i = indexOf(list, value, cmp)
if (i === -1) return -1
for (; i >= 0; i--) {
var c = cmp(list[i], value)
if (c < 0) return i
}
return -1
}
function gte (list, value, cmp) {
if (!cmp) cmp = defaultCmp
var i = indexOf(list, value, cmp)
if (i === -1) return -1
for (; i < list.length; i++) {
var c = cmp(list[i], value)
if (c >= 0) return i
}
return -1
}
function gt (list, value, cmp) {
if (!cmp) cmp = defaultCmp
var i = indexOf(list, value, cmp)
if (i === -1) return -1
for (; i < list.length; i++) {
var c = cmp(list[i], value)
if (c > 0) return i
}
return -1
}
function eq (list, value, cmp) {
if (!cmp) cmp = defaultCmp
var i = indexOf(list, value, cmp)
if (i === -1) return -1
return cmp(list[i], value) === 0 ? i : -1
}
function nearest (list, value, cmp) {
if (!cmp) cmp = defaultCmp
var len = list.length
var top = len - 1
var btm = 0
var mid = -1
var trending = 1 // 0 = down, 2 = up
while (top >= btm && btm >= 0 && top < len) {
mid = Math.floor((top + btm) / 2)
var c = cmp(list[mid], value)
if (c === 0) return mid
if (c >= 0) {
if (trending === 1) trending = 0
else if (trending === 2) {
if (Math.abs(list[mid] - value) > Math.abs(list[mid - 1] - value)) return mid - 1
return mid
}
top = mid - 1
} else {
if (trending === 1) trending = 2
else if (trending === 0) return mid
btm = mid + 1
}
}
return mid
}
function indexOf (list, value, cmp) {
if (!cmp) cmp = defaultCmp
var len = list.length
var top = len - 1
var btm = 0
var mid = -1
while (top >= btm && btm >= 0 && top < len) {
mid = Math.floor((top + btm) / 2)
var c = cmp(list[mid], value)
if (c === 0) return mid
if (c >= 0) {
top = mid - 1
} else {
btm = mid + 1
}
}
return mid
}
function has (list, value, cmp) {
return eq(list, value, cmp) > -1
}
function remove (list, value, cmp) {
var i = eq(list, value, cmp)
if (i === -1) return false
list.splice(i, 1)
return true
}