averello/swift-mirror
1
0
Fork 0
mirror of https://github.com/apple/swift.git synced 2025-12-21 12:14:44 +01:00
Code Issues Packages Projects Releases Wiki Activity

[stdlib][swift-3-indexing-model] changes in index(_:stepsFrom:limitedBy:)

Browse Source 
- index(_:stepsFrom:limitedBy:) returns Index?
- formIndex(_:stepsFrom:limitedBy) returns Bool
This commit is contained in:
Max Moiseev
2016-04-14 11:47:23 -07:00
parent 01d0de292c
commit 37bf02f7da
17 changed files with 141 additions and 99 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
stdlib/public/core/StringUTF16.swift
View File

@@ -78,11 +78,13 @@ extension String {
// TODO: swift-3-indexing-model - add docs
@warn_unused_result
public func index(n: IndexDistance, stepsFrom i: Index, limitedBy limit: Index) -> Index {
public func index(
n: IndexDistance, stepsFrom i: Index, limitedBy limit: Index
) -> Index? {
// FIXME: swift-3-indexing-model: range check i?
let d = i._offset.distance(to: limit._offset)
if d == 0 || (d > 0 ? d <= n : d >= n) {
return limit
if (d > 0) ? (d < n) : (d > n) {
return nil
}
return Index(_offset: i._offset.advanced(by: n))
}
@@ -403,7 +405,9 @@ extension String.UTF16View.Indices : BidirectionalCollection {
}
@warn_unused_result
public func index(n: IndexDistance, stepsFrom i: Index, limitedBy limit: Index) -> Index {
public func index(
n: IndexDistance, stepsFrom i: Index, limitedBy limit: Index
) -> Index? {
// FIXME: swift-3-indexing-model: range check i?
return _elements.index(n, stepsFrom: i, limitedBy: limit)
}