diff --git a/check_outdated.sh b/check_outdated.sh
index 6cfcd5c4..d4b898be 100755
--- a/check_outdated.sh
+++ b/check_outdated.sh
@@ -9,11 +9,14 @@
 
 set -xe
 
-if sed --version 2>/dev/null | grep -q GNU; then
-    SED_INPLACE="sed -i"
-else
-    SED_INPLACE="sed -i ''"
-fi
+SED_INPLACE() {
+  if sed --version 2>/dev/null | grep -q GNU; then
+    sed -i "$@"
+  else
+    sed -i '' "$@"
+  fi
+}
+
 version="$1"
 locale="$2"
 cur_path=`pwd`
@@ -31,7 +34,7 @@ for file in `find ./docs/content/doc -name "*.${locale}.md"`; do
     fi
     if [[ "$latest_commit_time_en" -gt "$latest_commit_time_locale" ]]; then
         echo "file: $file, lastest commit timestamp: $latest_commit_time_en (en ver), $latest_commit_time_locale ($locale ver)"
-        $SED_INPLACE '1s/---/---\nisOutdated: true/' $file
+        SED_INPLACE '1s/---/---\nisOutdated: true/' $file
     fi
 done
 
diff --git a/loop_docs.sh b/loop_docs.sh
index 56e7a64b..2ad5a220 100755
--- a/loop_docs.sh
+++ b/loop_docs.sh
@@ -6,11 +6,13 @@
 
 set -xe
 
-if sed --version 2>/dev/null | grep -q GNU; then
-    SED_INPLACE="sed -i"
-else
-    SED_INPLACE="sed -i ''"
-fi
+SED_INPLACE() {
+  if sed --version 2>/dev/null | grep -q GNU; then
+    sed -i "$@"
+  else
+    sed -i '' "$@"
+  fi
+}
 
 version="$1"
 if [ "$version" != "lastest" ]; then
@@ -42,38 +44,38 @@ else
 fi
 
 if [ -f "$docs_dir/installation/with-docker.$locale.md" ]; then
-    $SED_INPLACE 's/\\<empty>/<empty\\>/' "$docs_dir/installation/with-docker.$locale.md"
+    SED_INPLACE 's/\\<empty>/<empty\\>/' "$docs_dir/installation/with-docker.$locale.md"
 fi
-$SED_INPLACE 's/\\<empty/<empty/' "$docs_dir/administration/config-cheat-sheet.$locale.md"
-$SED_INPLACE 's/<empty>/<empty\\>/' "$docs_dir/administration/config-cheat-sheet.$locale.md"
-$SED_INPLACE 's/^url:.*//' "$docs_dir/intro.md"
-$SED_INPLACE 's/^slug:.*/slug: \//' "$docs_dir/intro.md"
-$SED_INPLACE "s/{{< min-node-version >}}/$minNodeVer/" "$docs_dir/development/hacking-on-gitea.$locale.md"
-$SED_INPLACE "s/{{< min-go-version >}}/$minGoVer/" "$docs_dir/development/hacking-on-gitea.$locale.md"
-$SED_INPLACE "s/{{< go-version >}}/$goVer/" "$docs_dir/development/hacking-on-gitea.$locale.md"
-$SED_INPLACE "s/{{< min-node-version >}}/$minNodeVer/" "$docs_dir/installation/from-source.$locale.md"
-$SED_INPLACE "s/{{< min-go-version >}}/$minGoVer/" "$docs_dir/installation/from-source.$locale.md"
+SED_INPLACE 's/\\<empty/<empty/' "$docs_dir/administration/config-cheat-sheet.$locale.md"
+SED_INPLACE 's/<empty>/<empty\\>/' "$docs_dir/administration/config-cheat-sheet.$locale.md"
+SED_INPLACE 's/^url:.*//' "$docs_dir/intro.md"
+SED_INPLACE 's/^slug:.*/slug: \//' "$docs_dir/intro.md"
+SED_INPLACE "s/{{< min-node-version >}}/$minNodeVer/" "$docs_dir/development/hacking-on-gitea.$locale.md"
+SED_INPLACE "s/{{< min-go-version >}}/$minGoVer/" "$docs_dir/development/hacking-on-gitea.$locale.md"
+SED_INPLACE "s/{{< go-version >}}/$goVer/" "$docs_dir/development/hacking-on-gitea.$locale.md"
+SED_INPLACE "s/{{< min-node-version >}}/$minNodeVer/" "$docs_dir/installation/from-source.$locale.md"
+SED_INPLACE "s/{{< min-go-version >}}/$minGoVer/" "$docs_dir/installation/from-source.$locale.md"
 
 # TODO: improve this sed
 # need confirmation
 if [ "$version" == "lastest" ]; then
-    $SED_INPLACE 's/"version":.*/"version":"1.21-dev"/' static/latest-swagger.json
+    SED_INPLACE 's/"version":.*/"version":"1.21-dev"/' static/latest-swagger.json
 elif [ "$version" == "1.20" ]; then
-    $SED_INPLACE 's/"version":.*/"version":"1.20.0-rc0"/' static/20-swagger.json
+    SED_INPLACE 's/"version":.*/"version":"1.20.0-rc0"/' static/20-swagger.json
 elif [ "$version" == "1.19" ]; then
-    $SED_INPLACE 's/"version":.*/"version":"1.19.3"/' static/19-swagger.json
+    SED_INPLACE 's/"version":.*/"version":"1.19.3"/' static/19-swagger.json
 fi
 
 for file in `find ./"$docs_dir" -name "*.md"`; do
     # hide hugo toc
-    $SED_INPLACE 's/{{< toc >}}//' $file
-    $SED_INPLACE 's/dl.gitea.com\/gitea\/{{< version >}}/dl.gitea.com\/gitea\/main/g' $file
-    $SED_INPLACE "s/{{< version >}}/$minorVer/g" $file
-    $SED_INPLACE 's/{{< relref "doc\///g' $file
-    $SED_INPLACE "s/.$locale.md/.md/g" $file
-    $SED_INPLACE 's/" >}}//g' $file
-    $SED_INPLACE 's/\*\*Table of Contents\*\*//' $file
-    $SED_INPLACE 's/weight:/sidebar_position:/g' $file
+    SED_INPLACE 's/{{< toc >}}//' $file
+    SED_INPLACE 's/dl.gitea.com\/gitea\/{{< version >}}/dl.gitea.com\/gitea\/main/g' $file
+    SED_INPLACE "s/{{< version >}}/$minorVer/g" $file
+    SED_INPLACE 's/{{< relref "doc\///g' $file
+    SED_INPLACE "s/.$locale.md/.md/g" $file
+    SED_INPLACE 's/" >}}//g' $file
+    SED_INPLACE 's/\*\*Table of Contents\*\*//' $file
+    SED_INPLACE 's/weight:/sidebar_position:/g' $file
     #sed -i 's/^slug:.*//' $file
 done