Add Go Playground links for examples

Author: tiendc

docs/DECODING.md

@@ -18,6 +18,8 @@
 
 ### First example
 
+[Playground](https://go.dev/play/p/tUw9SfaD8QK)
+
 ```go
     data := []byte(`
 name,birthdate,address
@@ -51,6 +53,8 @@ tom,1989-11-11T00:00:00Z,new york`)
 
 - Preprocessor functions will be called before cell values are decoded and validator functions will be called after that.
 
+[Playground](https://go.dev/play/p/Ndn2sj4030c)
+
 ```go
     data := []byte(`
 name,age,address
@@ -95,6 +99,8 @@ tom ,26,new york`)
 
 - When set `StopOnError = false`, the decoding will continue to process the data even when errors occur. You can handle all errors of the process at once.
 
+[Playground](https://go.dev/play/p/mV1UX69mHWS)
+
 ```go
     data := []byte(`
 name,age,address
@@ -130,6 +136,8 @@ tom,26,new york`)
 - Optional column is a column which is defined in the struct tag but not exist in the input data
 - Unrecognized column is a column which exists in the input data but is not defined in the struct tag
 
+[Playground](https://go.dev/play/p/OA8Jh3Y4aaD)
+
 ```go
     data := []byte(`
 name,age,mark
@@ -165,6 +173,8 @@ tom,26,9`)
 
 - By default, the header order in the input data must match the order defined in the struct tag.
 
+[Playground](https://go.dev/play/p/3va5HYWacPO)
+
 ```go
     // `address` appears before `age`
     data := []byte(`
@@ -200,6 +210,8 @@ tom,new york,9`)
 
 - Fixed inline columns are represented by an inner struct. `prefix` can be set for inline columns.
 
+[Playground](https://go.dev/play/p/ouZDv4zjfSA)
+
 ```go
     data := []byte(`
 name,age,mark_math,mark_chemistry,mark_physics
@@ -245,6 +257,8 @@ tom,19,7,8,9`)
 
 - Dynamic inline columns are represented by an inner struct with variable number of columns. `prefix` can also be set for them.
 
+[Playground](https://go.dev/play/p/5SCRzMp6NZP)
+
 ```go
     data := []byte(`
 name,age,mark_math,mark_chemistry,mark_physics
@@ -282,6 +296,8 @@ tom,19,7,8,9`)
 
 - Any user custom type can be decoded by implementing either `encoding.TextUnmarshaler` or `csvlib.CSVUnmarshaler` or both. `csvlib.CSVUnmarshaler` has higher priority.
 
+[Playground](https://go.dev/play/p/g_QmAN6di-9)
+
 ```go
 type BirthDate time.Time
 
@@ -329,6 +345,8 @@ tom,1989-11-11`)
 
 - By default, the decoder detects columns via comma delimiter, if you want to decode custom one, use `csv.Reader` from the built-in package `encoding/csv` as the input reader.
 
+[Playground](https://go.dev/play/p/HgxcyzeHho6)
+
 ```go
     data := []byte(
         "name\tage\taddress\n" +
@@ -361,6 +379,8 @@ tom,1989-11-11`)
 
 ### Decode one-by-one
 
+[Playground](https://go.dev/play/p/81jLLnGbENa)
+
 ```go
     data := []byte(`
 name,age,address
@@ -393,6 +413,8 @@ tom,26,new york`)
 
 - This functionality allows to decode multiple input data with header translated into specific language
 
+[Playground](https://go.dev/play/p/Tf-unVfBnYH)
+
 ```go
 // Sample localization data (you can define them somewhere else such as in a json file)
 var (
@@ -469,6 +491,8 @@ tom,19,new york`)
 
 - Decoding errors can be rendered as a more human-readable content such as text or CSV.
 
+[Playground](https://go.dev/play/p/cTNGAUlP7s_T)
+
 ```go
     data := []byte(`
 name,age,address
@@ -488,7 +512,7 @@ jj,40,`)
         cfg.StopOnError = false
         cfg.DetectRowLine = true
         cfg.ConfigureColumn("name", func(cfg *csvlib.DecodeColumnConfig) {
-            cfg.ValidatorFuncs = []csvlib.ValidatorFunc{csvlib.ValidatorRange(1, 10)}
+            cfg.ValidatorFuncs = []csvlib.ValidatorFunc{csvlib.ValidatorStrLen[string](3, 10)}
             cfg.OnCellErrorFunc = func(e *csvlib.CellError) {
                 if errors.Is(e, csvlib.ErrValidationStrLen) {
                     e.SetLocalizationKey("Column {{.Column}} - '{{.Value}}': Name length must be from {{.MinLen}} to {{.MaxLen}}")
@@ -521,6 +545,7 @@ jj,40,`)
 
 - Render error as CSV content.
 
+[Playground](https://go.dev/play/p/7sJTKNSrOYl)
 
 ```go
     renderer, _ := csvlib.NewCSVRenderer(err.(*csvlib.Errors), func(cfg *csvlib.CSVRenderConfig) {

docs/ENCODING.md

@@ -16,6 +16,8 @@
 
 ### First example
 
+[Playground](https://go.dev/play/p/SVTP87loZ-g)
+
 ```go
     type Student struct {
         Name      string    `csv:"name"`
@@ -41,6 +43,8 @@
 
 ### No header mode
 
+[Playground](https://go.dev/play/p/qkfXClVUO5e)
+
 ```go
     type Student struct {
         Name      string    `csv:"name"`
@@ -69,6 +73,8 @@
 
 - Postprocessor functions will be called after Go values are encoded into CSV string.
 
+[Playground](https://go.dev/play/p/MlppfYm-xey)
+
 ```go
     type Student struct {
         Name    string `csv:"name"`
@@ -100,6 +106,8 @@
 
 - To skip encoding a column, you can omit the `csv` tag from the struct field or use `csv:"-"`. You can also use an equivalent configuration option for the column.
 
+[Playground](https://go.dev/play/p/NHzpm9o-y6N)
+
 ```go
     type Student struct {
         Name    string `csv:"name"`
@@ -131,6 +139,8 @@
 
 - Fixed inline columns are represented by an inner struct. `prefix` can be set for inline columns.
 
+[Playground](https://go.dev/play/p/kenlqLQ9p75)
+
 ```go
     type Marks struct {
         Math      int `csv:"math"`
@@ -164,6 +174,8 @@
 
 - Dynamic inline columns are represented by an inner struct with variable number of columns. `prefix` can also be set for them.
 
+[Playground](https://go.dev/play/p/BaMNjFj5Kr0)
+
 ```go
     type Student struct {
         Name    string                   `csv:"name"`
@@ -193,11 +205,13 @@
 
 - Any user custom type can be decoded by implementing either `encoding.TextMarshaler` or `csvlib.CSVMarshaler` or both. `csvlib.CSVMarshaler` has higher priority.
 
+[Playground](https://go.dev/play/p/iSfxQSkUCax)
+
 ```go
 type BirthDate time.Time
 
 func (d BirthDate) MarshalCSV() ([]byte, error) {
-    return []byte(time.Time(d).Format("2006-02-01")), nil // RFC3339
+    return []byte(time.Time(d).Format("2006-01-02")), nil // RFC3339
 }
 ```
 ```go
@@ -227,6 +241,8 @@ func (d BirthDate) MarshalCSV() ([]byte, error) {
 
 - By default, the encoder uses comma as the delimiter, if you want to encode custom one, use `csv.Writer` from the built-in package `encoding/csv` as the input writer.
 
+[Playground](https://go.dev/play/p/WxOStP5cb6G)
+
 ```go
     type Student struct {
         Name    string `csv:"name"`
@@ -258,6 +274,8 @@ func (d BirthDate) MarshalCSV() ([]byte, error) {
 
 ### Encode one-by-one
 
+[Playground](https://go.dev/play/p/aQWk3qqlBVm)
+
 ```go
     type Student struct {
         Name    string `csv:"name"`
@@ -293,6 +311,8 @@ func (d BirthDate) MarshalCSV() ([]byte, error) {
 
 - This functionality allows to encode CSV data with header translated into a specific language.
 
+[Playground](https://go.dev/play/p/jH7joZPgWJO)
+
 ```go
 // Sample localization data (you can define them somewhere else such as in a json file)
 var (