package main
import (
"regexp"
"fmt"
)
func main() {
var re = regexp.MustCompile(`(?m)(?<=<P2 x=")[\d,-]+(?=.*<P3 x="([\d,-]+)")`)
var str = `<P1 x="-0,36935" y="0,26315"/><P2 x="4,29731" y="0,26315"/><P3 x="5,29731" y="-0,40351"/><P4 x="-0,36935" y="-0,40351"/>
<P1 x="4,64065" y="0,26315"/><P2 x="5,97398" y="0,26315"/><P3 x="5,30731" y="-0,40351"/><P4 x="4,64065" y="-0,40351"/>`
var substitution = "\1"
fmt.Println(re.ReplaceAllString(str, substitution))
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Golang, please visit: https://golang.org/pkg/regexp/