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Diffstat (limited to 'src/dma/vendor/golang.org/x/text/unicode/norm/trie.go')
-rw-r--r--src/dma/vendor/golang.org/x/text/unicode/norm/trie.go54
1 files changed, 54 insertions, 0 deletions
diff --git a/src/dma/vendor/golang.org/x/text/unicode/norm/trie.go b/src/dma/vendor/golang.org/x/text/unicode/norm/trie.go
new file mode 100644
index 00000000..423386bf
--- /dev/null
+++ b/src/dma/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)
+)
+
+// lookupValue 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
+}