docs: function interpolate(val, scope) {
  
          // if no scope or value with {{ then no interpolation and can just return translated
          if (!scope || !val || !val.match) { return val; }
  
          // first, we need to get all values with a {{ }} in the string
          var i18nVars = val.match(i18nVarExpr);
  
          // loop through {{ }} values
          _.each(i18nVars, function (i18nVar) {
              var field = i18nVar.substring(2, i18nVar.length - 2).trim();
              var scopeVal = getScopeValue(scope, field);
              val = val.replace(i18nVar, scopeVal);
          });
  
          return val;
      }