// By default, Underscore uses ERB-style template delimiters, change the

// following template settings to use alternative delimiters.

define([], function () {

let templateSettings = {

evaluate: /<%([\s\S]+?)%>/g,

interpolate: /<%=([\s\S]+?)%>/g,

escape: /<%-([\s\S]+?)%>/g

};

// When customizing `templateSettings`, if you don't want to define an

// interpolation, evaluation or escaping regex, we need one that is

// guaranteed not to match.

let noMatch = /(.)^/;

// Certain characters need to be escaped so that they can be put into a

// string literal.

let escapes = {

'\'': '\'',

'\\': '\\',

'\r': 'r',

'\n': 'n',

'\u2028': 'u2028',

'\u2029': 'u2029'

};

let escapeRegExp = /\\|'|\r|\n|\u2028|\u2029/g;

let escapeChar = function (match) {

return '\\' + escapes[match];

};

// JavaScript micro-templating, similar to John Resig's implementation.

// Underscore templating handles arbitrary delimiters, preserves whitespace,

// and correctly escapes quotes within interpolated code.

// NB: `oldSettings` only exists for backwards compatibility.

return function (text, settings) {

settings = Object.assign({}, settings, templateSettings);

// Combine delimiters into one regular expression via alternation.

let matcher = RegExp([

(settings.escape || noMatch).source,

(settings.interpolate || noMatch).source,

(settings.evaluate || noMatch).source

].join('|') + '|$', 'g');

// Compile the template source, escaping string literals appropriately.

let index = 0;

let source = '__p+=\'';

text.replace(matcher, function (match, escape, interpolate, evaluate, offset) {

source += text.slice(index, offset).replace(escapeRegExp, escapeChar);

index = offset + match.length;

if (escape) {

source += '\'+\n((__t=(' + escape + '))==null?\'\':_.escape(__t))+\n\'';

} else if (interpolate) {

source += '\'+\n((__t=(' + interpolate + '))==null?\'\':__t)+\n\'';

} else if (evaluate) {

source += '\';\n' + evaluate + '\n__p+=\'';

}

// Adobe VMs need the match returned to produce the correct offset.

return match;

});

source += '\';\n';

// If a variable is not specified, place data values in local scope.

if (!settings.variable) source = 'with(obj||{}){\n' + source + '}\n';

source = 'let __t,__p=\'\',__j=Array.prototype.join,' +

'print=function(){__p+=__j.call(arguments,\'\');};\n' +

source + 'return __p;\n';

let render;

try {

render = new Function(settings.variable || 'obj', source);

} catch (e) {

e.source = source;

throw e;

}

let template = function (data) {

return render.call(this, data);

};

// Provide the compiled source as a convenience for precompilation.

let argument = settings.variable || 'obj';

template.source = 'function(' + argument + '){\n' + source + '}';

return template;

};

});