1 files changed, 44 insertions, 31 deletions

diff --git a/predicate.go b/predicate.go
index f975e27..a6746be 100644
--- a/predicate.go
+++ b/predicate.go
@@ -6,61 +6,58 @@ import (
 )
 
 // Predicate determines what terms can follow a command or a flag
-type Predicate func(last string) []Option
+// It is used for auto completion, given last - the last word in the already
+// in the command line, what words can complete it.
+type Predicate func(last string) []Matcher
 
-// Or unions two predicate struct, so that the result predicate
+// Or unions two predicate functions, so that the result predicate
 // returns the union of their predication
 func (p Predicate) Or(other Predicate) Predicate {
 	if p == nil || other == nil {
 		return nil
 	}
-	return func(last string) []Option { return append(p.predict(last), other.predict(last)...) }
+	return func(last string) []Matcher { return append(p.predict(last), other.predict(last)...) }
 }
 
-func (p Predicate) predict(last string) []Option {
+func (p Predicate) predict(last string) []Matcher {
 	if p == nil {
 		return nil
 	}
 	return p(last)
 }
 
-var (
-	PredictNothing Predicate = nil
-)
+// PredictNothing does not expect anything after.
+var PredictNothing Predicate = nil
 
-func PredictAnything(last string) []Option { return nil }
+// PredictNothing expects something, but nothing particular, such as a number
+// or arbitrary name.
+func PredictAnything(last string) []Matcher { return nil }
 
+// PredictSet expects specific set of terms, given in the options argument.
 func PredictSet(options ...string) Predicate {
-	return func(last string) []Option {
-		ret := make([]Option, len(options))
+	return func(last string) []Matcher {
+		ret := make([]Matcher, len(options))
 		for i := range options {
-			ret[i] = Arg(options[i])
+			ret[i] = MatchPrefix(options[i])
 		}
 		return ret
 	}
 }
 
-func PredictDirs(last string) (options []Option) {
+// PredictDirs will search for directories in the given started to be typed
+// path, if no path was started to be typed, it will complete to directories
+// in the current working directory.
+func PredictDirs(last string) (options []Matcher) {
 	dir := dirFromLast(last)
 	return dirsAt(dir)
 }
 
-func dirsAt(path string) []Option {
-	dirs := []string{}
-	filepath.Walk(path, func(path string, info os.FileInfo, err error) error {
-		if info.IsDir() {
-			dirs = append(dirs, path)
-		}
-		return nil
-	})
-	if !filepath.IsAbs(path) {
-		filesToRel(dirs)
-	}
-	return filesToOptions(dirs)
-}
-
+// PredictFiles will search for files matching the given pattern in the started to
+// be typed path, if no path was started to be typed, it will complete to files that
+// match the pattern in the current working directory.
+// To match any file, use "*" as pattern. To match go files use "*.go", and so on.
 func PredictFiles(pattern string) Predicate {
-	return func(last string) []Option {
+	return func(last string) []Matcher {
 		dir := dirFromLast(last)
 		files, err := filepath.Glob(filepath.Join(dir, pattern))
 		if err != nil {
@@ -69,10 +66,26 @@ func PredictFiles(pattern string) Predicate {
 		if !filepath.IsAbs(pattern) {
 			filesToRel(files)
 		}
-		return filesToOptions(files)
+		return filesToMatchers(files)
+	}
+}
+
+func dirsAt(path string) []Matcher {
+	dirs := []string{}
+	filepath.Walk(path, func(path string, info os.FileInfo, err error) error {
+		if info.IsDir() {
+			dirs = append(dirs, path)
+		}
+		return nil
+	})
+	if !filepath.IsAbs(path) {
+		filesToRel(dirs)
 	}
+	return filesToMatchers(dirs)
 }
 
+// filesToRel, change list of files to their names in the relative
+// to current directory form.
 func filesToRel(files []string) {
 	wd, err := os.Getwd()
 	if err != nil {
@@ -95,10 +108,10 @@ func filesToRel(files []string) {
 	return
 }
 
-func filesToOptions(files []string) []Option {
-	options := make([]Option, len(files))
+func filesToMatchers(files []string) []Matcher {
+	options := make([]Matcher, len(files))
 	for i, f := range files {
-		options[i] = ArgFileName(f)
+		options[i] = MatchFileName(f)
 	}
 	return options
 }