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punctuation.go

@@ -7,8 +7,11 @@ import (
 	"strings"
 )
 
+// valid characters to extract
 const validPunc = ";:'\",!?.-()"
 
+// Extract scans the given File and returns only typical punctuation used in
+// prose.
 func Extract(f *os.File) string {
 	var out string
 	in := bufio.NewScanner(f)