diff options
Diffstat (limited to 'vendor/golang.org/x/text/unicode/norm/trie.go')
-rw-r--r-- | vendor/golang.org/x/text/unicode/norm/trie.go | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/vendor/golang.org/x/text/unicode/norm/trie.go b/vendor/golang.org/x/text/unicode/norm/trie.go new file mode 100644 index 0000000..e4250ae --- /dev/null +++ b/vendor/golang.org/x/text/unicode/norm/trie.go @@ -0,0 +1,54 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package norm + +type valueRange struct { + value uint16 // header: value:stride + lo, hi byte // header: lo:n +} + +type sparseBlocks struct { + values []valueRange + offset []uint16 +} + +var nfcSparse = sparseBlocks{ + values: nfcSparseValues[:], + offset: nfcSparseOffset[:], +} + +var nfkcSparse = sparseBlocks{ + values: nfkcSparseValues[:], + offset: nfkcSparseOffset[:], +} + +var ( + nfcData = newNfcTrie(0) + nfkcData = newNfkcTrie(0) +) + +// lookup determines the type of block n and looks up the value for b. +// For n < t.cutoff, the block is a simple lookup table. Otherwise, the block +// is a list of ranges with an accompanying value. Given a matching range r, +// the value for b is by r.value + (b - r.lo) * stride. +func (t *sparseBlocks) lookup(n uint32, b byte) uint16 { + offset := t.offset[n] + header := t.values[offset] + lo := offset + 1 + hi := lo + uint16(header.lo) + for lo < hi { + m := lo + (hi-lo)/2 + r := t.values[m] + if r.lo <= b && b <= r.hi { + return r.value + uint16(b-r.lo)*header.value + } + if b < r.lo { + hi = m + } else { + lo = m + 1 + } + } + return 0 +} |