mirror of
https://github.com/apple/swift.git
synced 2025-12-14 20:36:38 +01:00
7704e19b7d
This is only for the frontend, not for stdlib. The implementation is very slow, optimizing it is the next step. rdar://16755123 rdar://16013860 Swift SVN r18928
83 lines
2.5 KiB
C++
83 lines
2.5 KiB
C++
//===--- Unicode.h - Unicode utilities --------------------------*- C++ -*-===//
|
|
//
|
|
// This source file is part of the Swift.org open source project
|
|
//
|
|
// Copyright (c) 2014 - 2015 Apple Inc. and the Swift project authors
|
|
// Licensed under Apache License v2.0 with Runtime Library Exception
|
|
//
|
|
// See http://swift.org/LICENSE.txt for license information
|
|
// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef SWIFT_BASIC_UNICODE_H
|
|
#define SWIFT_BASIC_UNICODE_H
|
|
|
|
#include "swift/Basic/LLVM.h"
|
|
#include "llvm/ADT/StringRef.h"
|
|
|
|
namespace swift {
|
|
namespace unicode {
|
|
|
|
StringRef extractFirstExtendedGraphemeCluster(StringRef S);
|
|
|
|
static inline bool isSingleExtendedGraphemeCluster(StringRef S) {
|
|
StringRef First = extractFirstExtendedGraphemeCluster(S);
|
|
if (First.empty())
|
|
return false;
|
|
return First == S;
|
|
}
|
|
|
|
enum class GraphemeClusterBreakProperty : uint8_t {
|
|
Other,
|
|
CR,
|
|
LF,
|
|
Control,
|
|
Extend,
|
|
Regional_Indicator,
|
|
Prepend,
|
|
SpacingMark,
|
|
L,
|
|
V,
|
|
T,
|
|
LV,
|
|
LVT,
|
|
};
|
|
|
|
/// Extended grapheme cluster boundary rules, represented as a matrix. Indexed
|
|
/// by first code point, then by second code point in least-significant-bit
|
|
/// order. A set bit means that a boundary is prohibited between two code
|
|
/// points.
|
|
extern uint16_t ExtendedGraphemeClusterNoBoundaryRulesMatrix[];
|
|
|
|
/// Returns the value of the Grapheme_Cluster_Break property for a given code
|
|
/// point.
|
|
GraphemeClusterBreakProperty getGraphemeClusterBreakProperty(uint32_t C);
|
|
|
|
/// Returns true if there is always an extended grapheme cluster boundary
|
|
/// after a code point with a given property value. Use only for optimization,
|
|
/// to skip calculating Grapheme_Cluster_Break property for the second code
|
|
/// point.
|
|
static inline bool
|
|
isExtendedGraphemeClusterBoundaryAfter(GraphemeClusterBreakProperty GCB1) {
|
|
auto RuleRow =
|
|
ExtendedGraphemeClusterNoBoundaryRulesMatrix[static_cast<unsigned>(GCB1)];
|
|
return RuleRow == 0;
|
|
}
|
|
|
|
/// Determine if there is an extended grapheme cluster boundary between code
|
|
/// points with given Grapheme_Cluster_Break property values.
|
|
static inline bool
|
|
isExtendedGraphemeClusterBoundary(GraphemeClusterBreakProperty GCB1,
|
|
GraphemeClusterBreakProperty GCB2) {
|
|
auto RuleRow =
|
|
ExtendedGraphemeClusterNoBoundaryRulesMatrix[static_cast<unsigned>(GCB1)];
|
|
return !(RuleRow & (1 << static_cast<unsigned>(GCB2)));
|
|
}
|
|
|
|
} // namespace unicode
|
|
} // namespace swift
|
|
|
|
#endif
|
|
|