把手中的宏

Question

Handlebars.js有部分,您可以使用<script>模板片段和Javascript调用来单独定义和注册registerPartial.我发现这很麻烦,我更喜欢Jinja风格的定义宏,你用相同的模板语言.

那里有帮手可以让我这样做:

{{#macro macro-name}}
  This is {{ bar }} and this is {{ foo }}
{{/macro}}

{{macro-name bar="BAR"}} {{! foo would be searched in the outer context}}

我没有运气就搜索过.

Answer 1

好吧,经过几个小时的阅读部分和抓挠我的头后,我想出了这个:

Handlebars.registerHelper('macro', function (name, defaults) {
    // The following helper will be registered with the name
    // given as the first parameter of the macro helper.
    // Upon invocation, variables will be looked up in the
    // following order: invocation arguments, default values
    // given in the macro definition (stored in defaults.hash),
    // and finally in the invocation context.
    Handlebars.registerHelper(name, function (options) {
        // options.hash has the parameters passed to
        // the defined helper in invocation, who
        // override the default parameters and the current context.
        var e = $.extend(this, defaults.hash, options.hash);

        // and here's where all the magic happens:
        return new Handlebars.SafeString(defaults.fn(e));
    });
});

您可以像这样定义一个宏:

{{#macro "macro-name" param1="bar" param2="" param3="egg"}}
  {{ param1 }}
  {{#each param2 }}
    {{ param3 }}
    {{ some_value }} {{! this one is looked up in the current context }}
  {{/each}}
{{/macro}}

并像这样调用它:

{{macro-name param1="foo" param2=some_array_in_context}}

定义的第一个参数是宏名称.所有其他参数必须采用param = value格式.

我现在已经用了几个小时了.我发现了一些错误,但修复了它们,我发现它很有用.令我惊讶的是最终代码的结果有多少.真正神奇的部分是,您可以使用帮助程序不返回字符串,而是定义新的帮助程序.

它需要jQuery,但是嘿,什么不是:-)