diff --git a/CHANGELOG.md b/CHANGELOG.md
index f5f2174..9e6a534 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -20,7 +20,6 @@
 
 * SetColor method in ConsoleWriter is deprecated. Please use SetDisplayAttributes instead.
 * prompt.Choose shortcut function is deprecated.
-* FilterHasPrefix, FilterHasSuffix and FilterContains is deprecated. Move to "github.com/c-bata/go-prompt/filter" package.
 
 ## v0.2.1 (2018/02/14)
 
diff --git a/filter.go b/filter.go
index 0fac0df..583674a 100644
--- a/filter.go
+++ b/filter.go
@@ -1,15 +1,11 @@
 package prompt
 
-import (
-	"strings"
-)
+import "strings"
 
 // Filter is the type to filter the prompt.Suggestion array.
-// Deprecated, move to github.com/c-bata/go-prompt/filter package.
 type Filter func([]Suggest, string, bool) []Suggest
 
 // FilterHasPrefix checks whether the string completions.Text begins with sub.
-// Deprecated, move to github.com/c-bata/go-prompt/filter package.
 func FilterHasPrefix(completions []Suggest, sub string, ignoreCase bool) []Suggest {
 	if sub == "" {
 		return completions
@@ -32,7 +28,6 @@ func FilterHasPrefix(completions []Suggest, sub string, ignoreCase bool) []Sugge
 }
 
 // FilterHasSuffix checks whether the completion.Text ends with sub.
-// Deprecated, move to github.com/c-bata/go-prompt/filter package.
 func FilterHasSuffix(completions []Suggest, sub string, ignoreCase bool) []Suggest {
 	if sub == "" {
 		return completions
@@ -55,7 +50,6 @@ func FilterHasSuffix(completions []Suggest, sub string, ignoreCase bool) []Sugge
 }
 
 // FilterContains checks whether the completion.Text contains sub.
-// Deprecated, move to github.com/c-bata/go-prompt/filter package.
 func FilterContains(completions []Suggest, sub string, ignoreCase bool) []Suggest {
 	if sub == "" {
 		return completions
diff --git a/filter/filter.go b/filter/filter.go
deleted file mode 100644
index 348c5f8..0000000
--- a/filter/filter.go
+++ /dev/null
@@ -1,73 +0,0 @@
-package filter
-
-import (
-	"strings"
-
-	"github.com/c-bata/go-prompt"
-)
-
-// HasPrefix checks whether the string completions.Text begins with sub.
-func HasPrefix(suggests []prompt.Suggest, sub string, ignoreCase bool) []prompt.Suggest {
-	if sub == "" {
-		return suggests
-	}
-	if ignoreCase {
-		sub = strings.ToUpper(sub)
-	}
-
-	ret := make([]prompt.Suggest, 0, len(suggests))
-	for i := range suggests {
-		c := suggests[i].Text
-		if ignoreCase {
-			c = strings.ToUpper(c)
-		}
-		if strings.HasPrefix(c, sub) {
-			ret = append(ret, suggests[i])
-		}
-	}
-	return ret
-}
-
-// HasSuffix checks whether the completion.Text ends with sub.
-func HasSuffix(suggests []prompt.Suggest, sub string, ignoreCase bool) []prompt.Suggest {
-	if sub == "" {
-		return suggests
-	}
-	if ignoreCase {
-		sub = strings.ToUpper(sub)
-	}
-
-	ret := make([]prompt.Suggest, 0, len(suggests))
-	for i := range suggests {
-		c := suggests[i].Text
-		if ignoreCase {
-			c = strings.ToUpper(c)
-		}
-		if strings.HasSuffix(c, sub) {
-			ret = append(ret, suggests[i])
-		}
-	}
-	return ret
-}
-
-// Contains checks whether the completion.Text contains sub.
-func Contains(suggests []prompt.Suggest, sub string, ignoreCase bool) []prompt.Suggest {
-	if sub == "" {
-		return suggests
-	}
-	if ignoreCase {
-		sub = strings.ToUpper(sub)
-	}
-
-	ret := make([]prompt.Suggest, 0, len(suggests))
-	for i := range suggests {
-		c := suggests[i].Text
-		if ignoreCase {
-			c = strings.ToUpper(c)
-		}
-		if strings.Contains(c, sub) {
-			ret = append(ret, suggests[i])
-		}
-	}
-	return ret
-}