package frontmatter import ( "fmt" "strings" "gopkg.in/yaml.v1" ) // Frontmatter encapsulates cheatsheet frontmatter data type Frontmatter struct { Tags []string Syntax string } // Parse parses cheatsheet frontmatter func Parse(markdown string) (string, Frontmatter, error) { // specify the frontmatter delimiter delim := "---" // initialize a frontmatter struct var fm Frontmatter // if the markdown does not contain frontmatter, pass it through unmodified if !strings.HasPrefix(markdown, delim) { return strings.TrimSpace(markdown), fm, nil } // otherwise, split the frontmatter and cheatsheet text parts := strings.SplitN(markdown, delim, 3) // return an error if the frontmatter parses into the wrong number of parts if len(parts) != 3 { return markdown, fm, fmt.Errorf("failed to delimit frontmatter") } // return an error if the YAML cannot be unmarshalled if err := yaml.Unmarshal([]byte(parts[1]), &fm); err != nil { return markdown, fm, fmt.Errorf("failed to unmarshal frontmatter: %v", err) } return strings.TrimSpace(parts[2]), fm, nil }