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path: root/vendor/golang.org/x/text/search/pattern.go
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Diffstat (limited to 'vendor/golang.org/x/text/search/pattern.go')
-rw-r--r--vendor/golang.org/x/text/search/pattern.go155
1 files changed, 0 insertions, 155 deletions
diff --git a/vendor/golang.org/x/text/search/pattern.go b/vendor/golang.org/x/text/search/pattern.go
deleted file mode 100644
index 2497cfd..0000000
--- a/vendor/golang.org/x/text/search/pattern.go
+++ /dev/null
@@ -1,155 +0,0 @@
-// Copyright 2015 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 search
-
-import (
- "golang.org/x/text/internal/colltab"
-)
-
-// TODO: handle variable primary weights?
-
-func (p *Pattern) deleteEmptyElements() {
- k := 0
- for _, e := range p.ce {
- if !isIgnorable(p.m, e) {
- p.ce[k] = e
- k++
- }
- }
- p.ce = p.ce[:k]
-}
-
-func isIgnorable(m *Matcher, e colltab.Elem) bool {
- if e.Primary() > 0 {
- return false
- }
- if e.Secondary() > 0 {
- if !m.ignoreDiacritics {
- return false
- }
- // Primary value is 0 and ignoreDiacritics is true. In this case we
- // ignore the tertiary element, as it only pertains to the modifier.
- return true
- }
- // TODO: further distinguish once we have the new implementation.
- if !(m.ignoreWidth || m.ignoreCase) && e.Tertiary() > 0 {
- return false
- }
- // TODO: we ignore the Quaternary level for now.
- return true
-}
-
-// TODO: Use a Boyer-Moore-like algorithm (probably Sunday) for searching.
-
-func (p *Pattern) forwardSearch(it *colltab.Iter) (start, end int) {
- for start := 0; it.Next(); it.Reset(start) {
- nextStart := it.End()
- if end := p.searchOnce(it); end != -1 {
- return start, end
- }
- start = nextStart
- }
- return -1, -1
-}
-
-func (p *Pattern) anchoredForwardSearch(it *colltab.Iter) (start, end int) {
- if it.Next() {
- if end := p.searchOnce(it); end != -1 {
- return 0, end
- }
- }
- return -1, -1
-}
-
-// next advances to the next weight in a pattern. f must return one of the
-// weights of a collation element. next will advance to the first non-zero
-// weight and return this weight and true if it exists, or 0, false otherwise.
-func (p *Pattern) next(i *int, f func(colltab.Elem) int) (weight int, ok bool) {
- for *i < len(p.ce) {
- v := f(p.ce[*i])
- *i++
- if v != 0 {
- // Skip successive ignorable values.
- for ; *i < len(p.ce) && f(p.ce[*i]) == 0; *i++ {
- }
- return v, true
- }
- }
- return 0, false
-}
-
-// TODO: remove this function once Elem is internal and Tertiary returns int.
-func tertiary(e colltab.Elem) int {
- return int(e.Tertiary())
-}
-
-// searchOnce tries to match the pattern s.p at the text position i. s.buf needs
-// to be filled with collation elements of the first segment, where n is the
-// number of source bytes consumed for this segment. It will return the end
-// position of the match or -1.
-func (p *Pattern) searchOnce(it *colltab.Iter) (end int) {
- var pLevel [4]int
-
- m := p.m
- for {
- k := 0
- for ; k < it.N; k++ {
- if v := it.Elems[k].Primary(); v > 0 {
- if w, ok := p.next(&pLevel[0], colltab.Elem.Primary); !ok || v != w {
- return -1
- }
- }
-
- if !m.ignoreDiacritics {
- if v := it.Elems[k].Secondary(); v > 0 {
- if w, ok := p.next(&pLevel[1], colltab.Elem.Secondary); !ok || v != w {
- return -1
- }
- }
- } else if it.Elems[k].Primary() == 0 {
- // We ignore tertiary values of collation elements of the
- // secondary level.
- continue
- }
-
- // TODO: distinguish between case and width. This will be easier to
- // implement after we moved to the new collation implementation.
- if !m.ignoreWidth && !m.ignoreCase {
- if v := it.Elems[k].Tertiary(); v > 0 {
- if w, ok := p.next(&pLevel[2], tertiary); !ok || int(v) != w {
- return -1
- }
- }
- }
- // TODO: check quaternary weight
- }
- it.Discard() // Remove the current segment from the buffer.
-
- // Check for completion.
- switch {
- // If any of these cases match, we are not at the end.
- case pLevel[0] < len(p.ce):
- case !m.ignoreDiacritics && pLevel[1] < len(p.ce):
- case !(m.ignoreWidth || m.ignoreCase) && pLevel[2] < len(p.ce):
- default:
- // At this point, both the segment and pattern has matched fully.
- // However, the segment may still be have trailing modifiers.
- // This can be verified by another call to next.
- end = it.End()
- if it.Next() && it.Elems[0].Primary() == 0 {
- if !m.ignoreDiacritics {
- return -1
- }
- end = it.End()
- }
- return end
- }
-
- // Fill the buffer with the next batch of collation elements.
- if !it.Next() {
- return -1
- }
- }
-}