diff --git a/action.go b/action.go
index 294fc694..0c1d9bed 100644
--- a/action.go
+++ b/action.go
@@ -56,6 +56,47 @@ func (a Action) Cache(timeout time.Duration, keys ...pkgcache.Key) Action {
 	return a
 }
 
+// CacheF requires a function to determine if we should use the cached data (if any and if it's
+// still within timeout), and if asked to refresh it, to cache the proceeds of the invoked action.
+func (a Action) CacheF(timeout time.Duration, refresh func() bool, keys ...pkgcache.Key) Action {
+	if a.callback == nil {
+		return a
+	}
+
+	_, file, line, _ := runtime.Caller(1)
+	cachedCallback := a.callback
+
+	return ActionCallback(func(c Context) Action {
+		// Know when the last cached values were written (if any)
+		cacheFile, err := cache.File(file, line, keys...)
+		if err != nil {
+			return a
+		}
+
+		stat, err := os.Stat(cacheFile)
+
+		// No cached results, just ask to cache after call.
+		cacheIsOutdated := (timeout > 0 && stat.ModTime().Add(timeout).Before(time.Now()))
+		if os.IsNotExist(err) || cacheIsOutdated {
+			return a.Cache(timeout, keys...)
+		}
+
+		// If we are asked to refresh the cache with new results anyway, do it.
+		if refresh() {
+			invokedAction := (Action{callback: cachedCallback}).Invoke(c)
+			if invokedAction.meta.Messages.IsEmpty() {
+				if cacheFile, err := cache.File(file, line, keys...); err == nil {
+					_ = cache.Write(cacheFile, invokedAction.export())
+				}
+			}
+			return invokedAction.ToA()
+		}
+
+		// Else, once again let's the cache do it's work.
+		return a.Cache(timeout, keys...)
+	})
+}
+
 // Chdir changes the current working directory to the named directory for the duration of invocation.
 func (a Action) Chdir(dir string) Action {
 	return ActionCallback(func(c Context) Action {
@@ -93,14 +134,14 @@ func (a Action) Filter(values ...string) Action {
 	})
 }
 
-// FilterArgs filters Context.Args
+// FilterArgs filters Context.Args.
 func (a Action) FilterArgs() Action {
 	return ActionCallback(func(c Context) Action {
 		return a.Filter(c.Args...)
 	})
 }
 
-// FilterArgs filters Context.Parts
+// FilterArgs filters Context.Parts.
 func (a Action) FilterParts() Action {
 	return ActionCallback(func(c Context) Action {
 		return a.Filter(c.Parts...)
@@ -141,7 +182,7 @@ func (a Action) MultiParts(dividers ...string) Action {
 	})
 }
 
-// MultiPartsP is like MultiParts but with placeholders
+// MultiPartsP is like MultiParts but with placeholders.
 func (a Action) MultiPartsP(delimiter string, pattern string, f func(placeholder string, matches map[string]string) Action) Action {
 	// TODO add delimiter as suffix for proper nospace handling (some values/placeholders might appear with and without suffix)
 	return ActionCallback(func(c Context) Action {
diff --git a/internalActions.go b/internalActions.go
index 3a52e660..60b35994 100644
--- a/internalActions.go
+++ b/internalActions.go
@@ -14,68 +14,25 @@ import (
 	"github.com/spf13/cobra"
 )
 
-func actionPath(fileSuffixes []string, dirOnly bool) Action {
+// ActionCommands returns the completed subcommands of a given cobra command.
+func ActionCommands(cmd *cobra.Command) Action {
 	return ActionCallback(func(c Context) Action {
-		if len(c.Value) == 2 && util.HasVolumePrefix(c.Value) {
-			// TODO should be fixed in Abs or wherever this is happening
-			return ActionValues(c.Value + "/") // prevent `C:` -> `C:.`
-		}
-
-		abs, err := c.Abs(c.Value)
-		if err != nil {
-			return ActionMessage(err.Error())
-		}
-
-		displayFolder := filepath.ToSlash(filepath.Dir(c.Value))
-		if displayFolder == "." {
-			displayFolder = ""
-		} else if !strings.HasSuffix(displayFolder, "/") {
-			displayFolder = displayFolder + "/"
-		}
-
-		actualFolder := filepath.ToSlash(filepath.Dir(abs))
-		files, err := ioutil.ReadDir(actualFolder)
-		if err != nil {
-			return ActionMessage(err.Error())
-		}
-
-		showHidden := !strings.HasSuffix(abs, "/") && strings.HasPrefix(filepath.Base(abs), ".")
-
-		vals := make([]string, 0, len(files)*2)
-		for _, file := range files {
-			if !showHidden && strings.HasPrefix(file.Name(), ".") {
-				continue
-			}
-
-			resolvedFile := file
-			if resolved, err := filepath.EvalSymlinks(actualFolder + file.Name()); err == nil {
-				if stat, err := os.Stat(resolved); err == nil {
-					resolvedFile = stat
-				}
-			}
-
-			if resolvedFile.IsDir() {
-				vals = append(vals, displayFolder+file.Name()+"/", style.ForPath(filepath.Clean(actualFolder+"/"+file.Name()+"/"), c))
-			} else if !dirOnly {
-				if len(fileSuffixes) == 0 {
-					fileSuffixes = []string{""}
-				}
-				for _, suffix := range fileSuffixes {
-					if strings.HasSuffix(file.Name(), suffix) {
-						vals = append(vals, displayFolder+file.Name(), style.ForPath(filepath.Clean(actualFolder+"/"+file.Name()), c))
-						break
-					}
+		batch := Batch()
+		for _, subcommand := range cmd.Commands() {
+			if (!subcommand.Hidden || env.Hidden()) && subcommand.Deprecated == "" {
+				group := common.Group{Cmd: subcommand}
+				batch = append(batch, ActionStyledValuesDescribed(subcommand.Name(), subcommand.Short, group.Style()).Tag(group.Tag()))
+				for _, alias := range subcommand.Aliases {
+					batch = append(batch, ActionStyledValuesDescribed(alias, subcommand.Short, group.Style()).Tag(group.Tag()))
 				}
 			}
 		}
-		if strings.HasPrefix(c.Value, "./") {
-			return ActionStyledValues(vals...).Invoke(Context{}).Prefix("./").ToA()
-		}
-		return ActionStyledValues(vals...)
+		return batch.ToA()
 	})
 }
 
-func actionFlags(cmd *cobra.Command) Action {
+// ActionFlags returns the completed flags of a given cobra command.
+func ActionFlags(cmd *cobra.Command) Action {
 	return ActionCallback(func(c Context) Action {
 		cmd.InitDefaultHelpFlag()
 		cmd.InitDefaultVersionFlag()
@@ -133,19 +90,64 @@ func actionFlags(cmd *cobra.Command) Action {
 	}).Tag("flags")
 }
 
-func actionSubcommands(cmd *cobra.Command) Action {
+func actionPath(fileSuffixes []string, dirOnly bool) Action {
 	return ActionCallback(func(c Context) Action {
-		batch := Batch()
-		for _, subcommand := range cmd.Commands() {
-			if (!subcommand.Hidden || env.Hidden()) && subcommand.Deprecated == "" {
-				group := common.Group{Cmd: subcommand}
-				batch = append(batch, ActionStyledValuesDescribed(subcommand.Name(), subcommand.Short, group.Style()).Tag(group.Tag()))
-				for _, alias := range subcommand.Aliases {
-					batch = append(batch, ActionStyledValuesDescribed(alias, subcommand.Short, group.Style()).Tag(group.Tag()))
+		if len(c.Value) == 2 && util.HasVolumePrefix(c.Value) {
+			// TODO should be fixed in Abs or wherever this is happening
+			return ActionValues(c.Value + "/") // prevent `C:` -> `C:.`
+		}
+
+		abs, err := c.Abs(c.Value)
+		if err != nil {
+			return ActionMessage(err.Error())
+		}
+
+		displayFolder := filepath.ToSlash(filepath.Dir(c.Value))
+		if displayFolder == "." {
+			displayFolder = ""
+		} else if !strings.HasSuffix(displayFolder, "/") {
+			displayFolder = displayFolder + "/"
+		}
+
+		actualFolder := filepath.ToSlash(filepath.Dir(abs))
+		files, err := ioutil.ReadDir(actualFolder)
+		if err != nil {
+			return ActionMessage(err.Error())
+		}
+
+		showHidden := !strings.HasSuffix(abs, "/") && strings.HasPrefix(filepath.Base(abs), ".")
+
+		vals := make([]string, 0, len(files)*2)
+		for _, file := range files {
+			if !showHidden && strings.HasPrefix(file.Name(), ".") {
+				continue
+			}
+
+			resolvedFile := file
+			if resolved, err := filepath.EvalSymlinks(actualFolder + file.Name()); err == nil {
+				if stat, err := os.Stat(resolved); err == nil {
+					resolvedFile = stat
+				}
+			}
+
+			if resolvedFile.IsDir() {
+				vals = append(vals, displayFolder+file.Name()+"/", style.ForPath(filepath.Clean(actualFolder+"/"+file.Name()+"/"), c))
+			} else if !dirOnly {
+				if len(fileSuffixes) == 0 {
+					fileSuffixes = []string{""}
+				}
+				for _, suffix := range fileSuffixes {
+					if strings.HasSuffix(file.Name(), suffix) {
+						vals = append(vals, displayFolder+file.Name(), style.ForPath(filepath.Clean(actualFolder+"/"+file.Name()), c))
+						break
+					}
 				}
 			}
 		}
-		return batch.ToA()
+		if strings.HasPrefix(c.Value, "./") {
+			return ActionStyledValues(vals...).Invoke(Context{}).Prefix("./").ToA()
+		}
+		return ActionStyledValues(vals...)
 	})
 }
 
@@ -167,7 +169,7 @@ func initHelpCompletion(cmd *cobra.Command) {
 			if err != nil {
 				return ActionMessage(err.Error())
 			}
-			return actionSubcommands(lastCmd)
+			return ActionCommands(lastCmd)
 		}),
 	)
 }
diff --git a/traverse.go b/traverse.go
index 900b6384..81e4f987 100644
--- a/traverse.go
+++ b/traverse.go
@@ -147,14 +147,14 @@ loop:
 			return storage.getFlag(c, f.Name).Prefix(f.Prefix), context
 		}
 		LOG.Printf("completing flags for arg %#v\n", context.Value)
-		return actionFlags(c), context
+		return ActionFlags(c), context
 
 	// positional or subcommand
 	default:
 		LOG.Printf("completing positionals and subcommands for arg %#v\n", context.Value)
 		batch := Batch(storage.getPositional(c, len(context.Args)))
 		if c.HasAvailableSubCommands() && len(context.Args) == 0 {
-			batch = append(batch, actionSubcommands(c))
+			batch = append(batch, ActionCommands(c))
 		}
 		return batch.ToA(), context
 	}