code: func (element *Element) computeDeclarations() ([]*css.Declaration, error) {
  	result := []*css.Declaration{}
  
  	styles := make(map[string]*StyleDeclaration)
  
  	// First: parsed stylesheets rules
  	mergeStyleDeclarations(element.styleRules, styles)
  
  	// Then: inline rules
  	inlineRules, err := element.parseInlineStyle()
  	if err != nil {
  		return result, err
  	}
  
  	mergeStyleDeclarations(inlineRules, styles)
  
  	// map to array
  	for _, styleDecl := range styles {
  		result = append(result, styleDecl.Declaration)
  	}
  
  	// sort declarations by property name
  	sort.Sort(css.DeclarationsByProperty(result))
  
  	return result, nil
  }
docs: // Compute css declarations