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/Algorithm: add an overload for startsWith that accepts a

Browse Source 
comparison predicate

Swift SVN r20601
This commit is contained in:
Dmitri Hrybenko
2014-07-27 01:00:26 +00:00
parent ee176e7269
commit a4c1ef90e7
2 changed files with 71 additions and 66 deletions
Download Patch File Download Diff File Expand all files Collapse all files

21
stdlib/core/Algorithm.swift
View File

@@ -548,6 +548,27 @@ public func startsWith<
return prefixGenerator.next() ? false : true
}
/// Return true iff the the initial elements of `s` are equal to `prefix`,
/// using `pred` as equality `==` comparison.
public func startsWith<
S0: SequenceType, S1: SequenceType
where
S0.Generator.Element == S1.Generator.Element
>(s: S0, prefix: S1,
predicate: (S1.Generator.Element, S1.Generator.Element) -> Bool) -> Bool
{
var prefixGenerator = prefix.generate()
for e0 in s {
var e1 = prefixGenerator.next()
if !e1 { return true }
if !predicate(e0, e1!) {
return false
}
}
return prefixGenerator.next() ? false : true
}
public struct EnumerateGenerator<
Base: GeneratorType
> : GeneratorType, SequenceType {