How to safely parse wiki text and insert links with html/template.

wikitemplate.go

package main

import (
        "bytes"
        "fmt"
        "html/template"
        "log"
        "regexp"
)

func main() {
        // I/O
        input := "The MethodSet of the interface is known & checked (see InterfaceSatisfaction) at compile time."
        output := new(bytes.Buffer)

        // Template
        tpl, err := template.New("wiki").Parse(`
                {{define "link"}}<a href="{{.URI}}">{{.Link}}</a>{{end}}
                {{define "text"}}{{.}}{{end}}
        `)
        if err != nil {
                log.Fatalf("parse: %s", err)
        }

        // Regexp
        wikiword, err := regexp.Compile(`([[:upper:]][[:lower:]]+){2,}`)
        if err != nil {
                log.Fatalf("compile: %s", err)
        }

        idx := wikiword.FindAllStringSubmatchIndex(input, -1)

        // Split repeatedly and write
        start := 0
        for _, idx := range idx {
                link, end := idx[0], idx[1]
                tpl.ExecuteTemplate(output, "text", input[start:link])
                tpl.ExecuteTemplate(output, "link", map[string]string{
                        "URI":  "/wiki/" + input[link:end],
                        "Link": input[link:end],
                })
                start = end
        }
	tpl.ExecuteTemplate(output, "text", input[start:])
        fmt.Println(output)
}