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@austinzheng
Last active June 10, 2016 01:23
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/*
This is free and unencumbered software released into the public domain.
Anyone is free to copy, modify, publish, use, compile, sell, or
distribute this software, either in source code form or as a compiled
binary, for any purpose, commercial or non-commercial, and by any
means.
In jurisdictions that recognize copyright laws, the author or authors
of this software dedicate any and all copyright interest in the
software to the public domain. We make this dedication for the benefit
of the public at large and to the detriment of our heirs and
successors. We intend this dedication to be an overt act of
relinquishment in perpetuity of all present and future rights to this
software under copyright law.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.
For more information, please refer to <http://unlicense.org/>
*/
class StringTupleCollection : CollectionType {
let backing : [String : [String]]
lazy private(set) var startIndex : StringTupleIndex = {
StringTupleIndex(self.backing)
}()
lazy private(set) var endIndex : StringTupleIndex = {
StringTupleIndex.endIndexFor(dict: self.backing)
}()
subscript(i: StringTupleIndex) -> (String, String) {
let array = backing[i.dictIndex]
return (array.0, array.1[i.arrayIndex])
}
init(_ backing: [String : [String]]) {
self.backing = backing
}
}
struct StringTupleIndex : ForwardIndexType, Comparable {
let backing : [String : [String]]
let dictIndex : Dictionary<String, [String]>.Index
let arrayIndex : Array<String>.Index
init(_ backing: [String : [String]],
dictIndex: Dictionary<String, [String]>.Index,
arrayIndex: Array<String>.Index) {
self.backing = backing
self.dictIndex = dictIndex
self.arrayIndex = arrayIndex
}
init(_ backing: [String : [String]]) {
self.backing = backing
var idx = backing.startIndex
while idx != backing.endIndex {
let array = backing[idx].1
if !array.isEmpty {
dictIndex = idx
arrayIndex = 0
return
} else {
idx = idx.successor()
}
}
dictIndex = backing.startIndex
arrayIndex = 0
}
static func endIndexFor(dict backing: [String : [String]]) -> StringTupleIndex {
var idx = backing.startIndex
var prevValidIdx : DictionaryIndex<String, [String]>?
// TODO: make this not awful
while idx != backing.endIndex {
if backing[idx].1.count > 0 {
prevValidIdx = idx
}
idx = idx.successor()
}
if let prevValidIdx = prevValidIdx {
return StringTupleIndex(backing, dictIndex: prevValidIdx, arrayIndex: backing[prevValidIdx].1.count)
} else {
return StringTupleIndex(backing)
}
}
func successor() -> StringTupleIndex {
let array = backing[dictIndex].1
if arrayIndex < array.count - 1 {
// Same array
return StringTupleIndex(backing, dictIndex: dictIndex, arrayIndex: arrayIndex + 1)
} else {
// Next dict
var nextIndex = dictIndex.successor()
while nextIndex != backing.endIndex {
// Does this key have an array?
let thisArray = backing[nextIndex].1
if !thisArray.isEmpty {
return StringTupleIndex(backing, dictIndex: nextIndex, arrayIndex: 0)
}
nextIndex = nextIndex.successor()
}
return StringTupleIndex.endIndexFor(dict: backing)
}
}
}
func ==(lhs: StringTupleIndex, rhs: StringTupleIndex) -> Bool {
return lhs.dictIndex == rhs.dictIndex && lhs.arrayIndex == rhs.arrayIndex
}
func <(lhs: StringTupleIndex, rhs: StringTupleIndex) -> Bool {
if lhs.dictIndex == rhs.dictIndex {
return lhs.arrayIndex < rhs.arrayIndex
}
return lhs.dictIndex < rhs.dictIndex
}
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