Golang - Find file names in tree with regex using walk

package main

import (
    "flag"
    "fmt"
    "os"
    "path/filepath"
    "regexp"
)

type blah struct {
    found   []string
    pattern regexp.Regexp
}

func (b *blah) visit(path string, f os.FileInfo, err error) error {
    if b.pattern.MatchString(f.Name()) {
        b.found = append(b.found, f.Name())
    }

    return nil
}

func createBlah(pattern *regexp.Regexp) blah {
    b := blah{}
    b.found = []string{}
    b.pattern = *pattern
    return b
}

func main() {
    flag.Parse()
    pattern := flag.Arg(0)
    root := flag.Arg(1)

    fmt.Println("compile", pattern)
    regxPattern, err := regexp.Compile(pattern)
    if err != nil {
        panic(err)
    }

    b := createBlah(regxPattern)
    filepath.Walk(root, b.visit)
    fmt.Println("Found paths:", b.found)
}