Can't parse double slash "//"

[aimestereo]

Hello, I've took simpleexpr example as my starting point and extended it to cover all my cases.

But for some reason I can't parse simple math operation: floor division: //

I've prepared a simplified example to highlight my exact case:

Demo repo: https://github.com/aimestereo/go-dsl-floor-division-issue

package main

import (
	"github.com/alecthomas/participle/v2"
)

type Expr struct {
    // doesn't matter if it's "/" "/" or "//"
	Op string `@(  "+" | "!" "=" | "&" "&" | "/" "/" | "/" )`
}

var (
	parser = participle.MustBuild[Expr]()
)

EBNF:

Expr = ("+" | ("!" "=") | ("&" "&") | ("/" "/") | "/") .

Diagram:

Tests that I'm checking:

• + - ok
• != - ok
• && - ok
• / - ok
• // - fails

[alecthomas]

You will need to define a custom lexer, the default lexer is the Go one which treats // as comments