bytes: add function to get indexes of word in string

Unlike Indexes, the word parameter must be separated by space or placed
at beginning or end of string.

1 files changed, 32 insertions, 0 deletions

diff --git a/lib/bytes/bytes.go b/lib/bytes/bytes.go
index 4db067a0..54a7856a 100644
--- a/lib/bytes/bytes.go
+++ b/lib/bytes/bytes.go
@@ -9,6 +9,7 @@ import (
 	"bytes"
 	"fmt"
 	"reflect"
+	"unicode"
 )
 
 //
@@ -510,6 +511,37 @@ func TokenFind(line, token []byte, startat int) (at int) {
 }
 
 //
+// WordIndexes returns the index of the all instance of word in s as long as
+// word is separated by space or at the beginning or end of s.
+//
+func WordIndexes(s []byte, word []byte) (idxs []int) {
+	tmp := Indexes(s, word)
+	if len(tmp) == 0 {
+		return nil
+	}
+
+	for _, idx := range tmp {
+		x := idx - 1
+		if x >= 0 {
+			if !unicode.IsSpace(rune(s[x])) {
+				continue
+			}
+		}
+		x = idx + len(word)
+		if x >= len(s) {
+			idxs = append(idxs, idx)
+			continue
+		}
+		if !unicode.IsSpace(rune(s[x])) {
+			continue
+		}
+		idxs = append(idxs, idx)
+	}
+
+	return idxs
+}
+
+//
 // WriteUint16 into slice of byte.
 //
 func WriteUint16(data *[]byte, x uint, v uint16) {