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path: root/vendor/github.com/rivo/uniseg/word.go
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-rw-r--r--vendor/github.com/rivo/uniseg/word.go89
1 files changed, 89 insertions, 0 deletions
diff --git a/vendor/github.com/rivo/uniseg/word.go b/vendor/github.com/rivo/uniseg/word.go
new file mode 100644
index 000000000..34fba7f29
--- /dev/null
+++ b/vendor/github.com/rivo/uniseg/word.go
@@ -0,0 +1,89 @@
+package uniseg
+
+import "unicode/utf8"
+
+// FirstWord returns the first word found in the given byte slice according to
+// the rules of [Unicode Standard Annex #29, Word Boundaries]. This function can
+// be called continuously to extract all words from a byte slice, as illustrated
+// in the example below.
+//
+// If you don't know the current state, for example when calling the function
+// for the first time, you must pass -1. For consecutive calls, pass the state
+// and rest slice returned by the previous call.
+//
+// The "rest" slice is the sub-slice of the original byte slice "b" starting
+// after the last byte of the identified word. If the length of the "rest" slice
+// is 0, the entire byte slice "b" has been processed. The "word" byte slice is
+// the sub-slice of the input slice containing the identified word.
+//
+// Given an empty byte slice "b", the function returns nil values.
+//
+// [Unicode Standard Annex #29, Word Boundaries]: http://unicode.org/reports/tr29/#Word_Boundaries
+func FirstWord(b []byte, state int) (word, rest []byte, newState int) {
+ // An empty byte slice returns nothing.
+ if len(b) == 0 {
+ return
+ }
+
+ // Extract the first rune.
+ r, length := utf8.DecodeRune(b)
+ if len(b) <= length { // If we're already past the end, there is nothing else to parse.
+ return b, nil, wbAny
+ }
+
+ // If we don't know the state, determine it now.
+ if state < 0 {
+ state, _ = transitionWordBreakState(state, r, b[length:], "")
+ }
+
+ // Transition until we find a boundary.
+ var boundary bool
+ for {
+ r, l := utf8.DecodeRune(b[length:])
+ state, boundary = transitionWordBreakState(state, r, b[length+l:], "")
+
+ if boundary {
+ return b[:length], b[length:], state
+ }
+
+ length += l
+ if len(b) <= length {
+ return b, nil, wbAny
+ }
+ }
+}
+
+// FirstWordInString is like [FirstWord] but its input and outputs are strings.
+func FirstWordInString(str string, state int) (word, rest string, newState int) {
+ // An empty byte slice returns nothing.
+ if len(str) == 0 {
+ return
+ }
+
+ // Extract the first rune.
+ r, length := utf8.DecodeRuneInString(str)
+ if len(str) <= length { // If we're already past the end, there is nothing else to parse.
+ return str, "", wbAny
+ }
+
+ // If we don't know the state, determine it now.
+ if state < 0 {
+ state, _ = transitionWordBreakState(state, r, nil, str[length:])
+ }
+
+ // Transition until we find a boundary.
+ var boundary bool
+ for {
+ r, l := utf8.DecodeRuneInString(str[length:])
+ state, boundary = transitionWordBreakState(state, r, nil, str[length+l:])
+
+ if boundary {
+ return str[:length], str[length:], state
+ }
+
+ length += l
+ if len(str) <= length {
+ return str, "", wbAny
+ }
+ }
+}