diff --git a/bin/is b/bin/is
index 8ddd6a5..bd069b3 100755
--- a/bin/is
+++ b/bin/is
@@ -35,6 +35,11 @@ Conditions:
 
 Negation:
   is not equal VALUE_A VALUE_B
+
+Optional article:
+  is not a number VALUE
+  is an existing PATH
+  is the file PATH
 EOF
         exit
     fi
diff --git a/bin/mo b/bin/mo
index 3fd65c2..458472e 100755
--- a/bin/mo
+++ b/bin/mo
@@ -29,6 +29,10 @@
 # Public: Template parser function.  Writes templates to stdout.
 #
 # $0             - Name of the mo file, used for getting the help message.
+# --allow-function-arguments
+#                - Permit functions in templates to be called with additional
+#                  arguments. This puts template data directly in to the path
+#                  of an eval statement. Use with caution.
 # --fail-not-set - Fail upon expansion of an unset variable.  Default behavior
 #                  is to silently ignore and expand into empty string.
 # --false        - Treat "false" as an empty value.  You may set the
@@ -43,6 +47,12 @@
 #
 # Mo uses the following environment variables:
 #
+# MO_ALLOW_FUNCTION_ARGUMENTS
+#                     - When set to a non-empty value, this allows functions
+#                       referenced in templates to receive additional
+#                       options and arguments. This puts the content from the
+#                       template directly into an eval statement. Use with
+#                       extreme care.
 # MO_FAIL_ON_UNSET    - When set to a non-empty value, expansion of an unset
 #                       env variable will be aborted with an error.
 # MO_FALSE_IS_EMPTY   - When set to a non-empty value, the string "false"
@@ -74,6 +84,11 @@ mo() (
                         exit 0
                         ;;
 
+                    --allow-function-arguments)
+                        # shellcheck disable=SC2030
+                        MO_ALLOW_FUNCTION_ARGUMENTS=true
+                        ;;
+
                     --fail-not-set)
                         # shellcheck disable=SC2030
                         MO_FAIL_ON_UNSET=true
@@ -115,6 +130,29 @@ mo() (
 )
 
 
+# Internal: Call a function.
+#
+# $1 - Function to call
+# $2 - Content to pass
+# $3 - Additional arguments as a single string
+#
+# This can be dangerous, especially if you are using tags like
+# {{someFunction ; rm -rf / }}
+#
+# Returns nothing.
+moCallFunction() {
+    local moCommand
+
+    # shellcheck disable=SC2031
+    if [[ -n "$MO_ALLOW_FUNCTION_ARGUMENTS" ]]; then
+        printf -v moCommand "%q %q %s" "$1" "$2" "$3"
+        eval "$moCommand"
+    else
+        "$1" "$2"
+    fi
+}
+
+
 # Internal: Scan content until the right end tag is found.  Creates an array
 # with the following members:
 #
@@ -567,7 +605,7 @@ moLoop() {
 moParse() {
     # Keep naming variables mo* here to not overwrite needed variables
     # used in the string replacements
-    local moBlock moContent moCurrent moIsBeginning moNextIsBeginning moTag
+    local moArgs moBlock moContent moCurrent moIsBeginning moNextIsBeginning moTag
 
     moCurrent=$2
     moIsBeginning=$3
@@ -585,6 +623,13 @@ moParse() {
                 # Sets context
                 moStandaloneAllowed moContent "${moContent[@]}" "$moIsBeginning"
                 moTrimWhitespace moTag "${moTag:1}"
+                
+                # Split arguments from the tag name. Arguments are passed to
+                # functions.
+                moArgs=$moTag
+                moTag=${moTag%% *}
+                moTag=${moTag%%$'\t'*}
+                moArgs=${moArgs:${#moTag}}
                 moFindEndTag moBlock "$moContent" "$moTag"
                 moFullTagName moTag "$moCurrent" "$moTag"
 
@@ -593,13 +638,13 @@ moParse() {
                     if moIsFunction "$moTag"; then
                         #: Consider piping the output to moGetContent
                         #: so the lambda does not execute in a subshell?
-                        moContent=$($moTag "${moBlock[0]}")
+                        moContent=$(moCallFunction "$moTag" "${moBlock[0]}" "$moArgs")
                         moParse "$moContent" "$moCurrent" false
                         moContent="${moBlock[2]}"
                     elif moIsArray "$moTag"; then
                         eval "moLoop \"\${moBlock[0]}\" \"$moTag\" \"\${!${moTag}[@]}\""
                     else
-                        moParse "${moBlock[0]}" "$moCurrent" false
+                        moParse "${moBlock[0]}" "$moCurrent" true
                     fi
                 fi
 
@@ -658,11 +703,16 @@ moParse() {
                 moContent="${moTag:1}"'}}'"$moContent"
                 moSplit moContent "$moContent" '}}}'
                 moTrimWhitespace moTag "${moContent[0]}"
+                moArgs=$moTag
+                moTag=${moTag%% *}
+                moTag=${moTag%%$'\t'*}
+                moArgs=${moArgs:${#moTag}}
                 moFullTagName moTag "$moCurrent" "$moTag"
                 moContent=${moContent[1]}
 
                 # Now show the value
-                moShow "$moTag" "$moCurrent"
+                # Quote moArgs here, do not quote it later.
+                moShow "$moTag" "$moCurrent" "$moArgs"
                 ;;
 
             '&'*)
@@ -676,8 +726,14 @@ moParse() {
             *)
                 # Normal environment variable or function call
                 moStandaloneDenied moContent "${moContent[@]}"
+                moArgs=$moTag
+                moTag=${moTag%% *}
+                moTag=${moTag%%$'\t'*}
+                moArgs=${moArgs:${#moTag}}
                 moFullTagName moTag "$moCurrent" "$moTag"
-                moShow "$moTag" "$moCurrent"
+
+                # Quote moArgs here, do not quote it later.
+                moShow "$moTag" "$moCurrent" "$moArgs"
                 ;;
         esac
 
@@ -763,6 +819,7 @@ moPartial() {
 #
 # $1 - Name of environment variable or function
 # $2 - Current context
+# $3 - Arguments string if $1 is a function
 #
 # Returns nothing.
 moShow() {
@@ -770,7 +827,7 @@ moShow() {
     local moJoined moNameParts
 
     if moIsFunction "$1"; then
-        CONTENT=$($1 "")
+        CONTENT=$(moCallFunction "$1" "" "$3")
         moParse "$CONTENT" "$2" false
         return 0
     fi
diff --git a/lib/completions b/lib/completions
index 538f2a0..372f9b4 160000
--- a/lib/completions
+++ b/lib/completions
@@ -1 +1 @@
-Subproject commit 538f2a0287bf8d3775e3745e212e27ad29f5003d
+Subproject commit 372f9b47e9c528e0516652155308d239abc5b727
diff --git a/lib/gitignore b/lib/gitignore
index 9da1b5d..fad7792 160000
--- a/lib/gitignore
+++ b/lib/gitignore
@@ -1 +1 @@
-Subproject commit 9da1b5d8ce4e009ff627c4fe49a4488b2a3f60d4
+Subproject commit fad779220742a6d54ccfc0c1a0e5b3d820253de6
diff --git a/lib/ohmyzsh b/lib/ohmyzsh
index 4cb7307..7cea847 160000
--- a/lib/ohmyzsh
+++ b/lib/ohmyzsh
@@ -1 +1 @@
-Subproject commit 4cb730773b52a47f2e9ab159a6b1c5185a3a37fb
+Subproject commit 7cea8475fbf8e1ba9e665e7740e35182c57bfb6f