Invalid grammar rule

[xcoulon]

// ------------------------------------------
// Front Matter
// ------------------------------------------
FrontMatter <- YamlFrontMatter 

FrontMatter <- YamlFrontMatterToken content:(YamlFrontMatterContent) YamlFrontMatterToken {
    return types.NewYamlFrontMatter(content.(string))
}

the second FrontMatter rule should be named YamlFrontMatter to be used in the first rule.