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currency/coincurency.go

@@ -1,7 +1,10 @@
 package currency
 
+// CoinCurrency represents a currency for selecting a decimal currency
+// when the flag WithCurrency in options.ConvertOptions is true.
 type CoinCurrency string
 
+// CoinCurrencies is a map between currency and coin currency
 var CoinCurrencies = map[Currency]CoinCurrency{
 	USD: "cents",
 	THB: "satangs",

currency/currency.go

@@ -1,12 +1,17 @@
 package currency
 
+// Currency represents a currency for selecting an integer currency
+// when the flag WithCurrency in options.ConvertOptions is true
 type Currency string
 
 const (
+	// USD represents a U.S. Dollar currency
 	USD Currency = "USD"
+	// THB represents a Thai Baht currency
 	THB Currency = "THB"
 )
 
+// Point uses when the flag WithCurrency in options.ConvertOptions is false
 const Point = "point"
 
 // String gets a string value

lang/lang.go

@@ -1,8 +1,9 @@
 package lang
 
-// Lang represents
+// Lang represents a language for selecting a word language
 type Lang string
 
 const (
+	// AmericanEnglish is an `en-us`
 	AmericanEnglish Lang = "en-us"
 )

numconword.go

@@ -11,6 +11,7 @@ import (
 )
 
 var (
+	// ErrInvalidNumber is an error when input an invalid number
 	ErrInvalidNumber = errors.New("numconword: invalid number")
 )