Function $interpolate

tools/ngui/static/js/lib/angular.js:4940–4992

* @ngdoc function * @name ng.$interpolate * @function * * @requires $parse * * @description * * Compiles a string with markup into an interpolation function. This service is used by the * HTML ng.$compile $compile service for data binding. See

(text, mustHaveExpression)

     *
     */
    function $interpolate(text, mustHaveExpression) {
      var startIndex,
          endIndex,
          index = 0,
          parts = [],
          length = text.length,
          hasInterpolation = false,
          fn,
          exp,
          concat = [];

      while(index < length) {
        if ( ((startIndex = text.indexOf(startSymbol, index)) != -1) &&
             ((endIndex = text.indexOf(endSymbol, startIndex + startSymbolLength)) != -1) ) {
          (index != startIndex) && parts.push(text.substring(index, startIndex));
          parts.push(fn = $parse(exp = text.substring(startIndex + startSymbolLength, endIndex)));
          fn.exp = exp;
          index = endIndex + endSymbolLength;
          hasInterpolation = true;
        } else {
          // we did not find anything, so we have to add the remainder to the parts array
          (index != length) && parts.push(text.substring(index));
          index = length;
        }
      }

      if (!(length = parts.length)) {
        // we added, nothing, must have been an empty string.
        parts.push('');
        length = 1;
      }

      if (!mustHaveExpression  || hasInterpolation) {
        concat.length = length;
        fn = function(context) {
          for(var i = 0, ii = length, part; i<ii; i++) {
            if (typeof (part = parts[i]) == 'function') {
              part = part(context);
              if (part == null || part == undefined) {
                part = '';
              } else if (typeof part != 'string') {
                part = toJson(part);
              }
            }
            concat[i] = part;
          }
          return concat.join('');
        };
        fn.exp = text;
        fn.parts = parts;
        return fn;
      }
    }


    /**