Simple Regexp fails but more complex one finds match

[Pat Farrell]

This has to be something simple, but I've been pulling my hair out for days.

I have made two regexp.MustCompile where one is just a simple punctuation

search and the other is a combination of an identifier plus the punctuation search.
I am building the patterns with two strings that I concatinate as argument to the MustCompile.

The complex Find works, but the simplier one returns nothing.

This is the opposite of what I expected.

Playground:

https://go.dev/play/p/4gp43BvwRwo

The code is near trivial, 
The output in the playground shows an empty slice when Find is 

called on the punctuation, yet 

returns the expected slice on the more complex pattern:

output:

>< 

Heart - 

Program exited.

Source: 

package main

import (
    "fmt"
    "regexp"
)

func main() {
    var fn = []byte("Heart - Crazy On You")
    const nameP = "(([0-9A-Za-z]*)\\s*)*"
    const divP = "-*"
    var regMulti = regexp.MustCompile(nameP + divP)
    var regPunch = regexp.MustCompile(divP)

    p := regPunch.Find(fn)
    fmt.Printf(">%s<\n", p)

    m := regMulti.Find(fn)
    fmt.Printf("%s\n", m)
}

Any enlightenment would be greatly appreciated.

[burak serdar]

This:

(-)*

matches the empty string as well, and that's what it is returning. Try (-)+

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[Pat Farrell]

That's it.

Thanks a ton