gtsv

Overview ¶

Package gtsv is the package to read TSV formatted text.

It is designed to type-specifically use each tsv columns, and easily find row and column number which error happened.

This is the example to treat valid TSV.

package main

import (
  "bytes"
  "fmt"

  "github.com/yagi5/gtsv"
)

func main() {
  tsv := "1\t2.1\ta\n" +
    "4\t5.2\tb\n" +
    "7\t8.3\tc\n"

  gt := gtsv.New(bytes.NewBufferString(tsv))

  for gt.Next() {
    fmt.Println(gt.Int())
    fmt.Println(gt.Float64())
    fmt.Println(gt.String())
  }
  fmt.Println(gt.Error())
}

While gt.Next() returns true, you can load column value type-specific, like `gt.Int()` , `gt.String()` .

Of course, you can use this with struct.

type user struct {
  name string
  age  int
  male bool
}

func main() {
  tsv := "john\t18\ttrue\n" +
    "emily\t16\tfalse\n"

  gt := gtsv.New(bytes.NewBufferString(tsv))

 var users []*user
  for gt.Next() {
    users = append(users, &user{name: gt.String(), age: gt.Int(), male: gt.Bool()})
  }

  fmt.Println(gr.Error())
}

If you change the order to call `gt.String()` and `gt.Int()` , `gt.Error()` will be non-nil because it's not the same as TSV column order.

Sometimes, we want to know the error position of these files. If you need it, you can cast `gt.Error()` (this is just a `error`) into `gtsv.Error` to know error position. like this:

tsvInvalid := "1\t2.1\ta\n" +
  "4\t5.2\tb\n" +
  "a\t8.3\tc\n" // first column is not int

gt := gtsv.New(bytes.NewBufferString(tsvInvalid))

for gt.Next() {
  fmt.Println(gt.Int())
  fmt.Println(gt.Float64())
  fmt.Println(gt.String())
}

if err := gt.Error(); err != nil {
  er := err.(gtsv.Error)
  fmt.Printf("error row: %d, col: %d", er.Row(), er.Col())
}

if cast `err.(gtsv.Error)` succeeded, `Row()` and `Col()` show you error position.