How to efficiently implement clientside javascript templating partials?

I'd like to build my own, but I'm not sure about the best way to do it. A partial is a template that is only a part of another bigger template and which can be inserted into multiple other templates at will. Templating itself is fairly basic, just string exctraction and concatenation, but clientside partials have me a little stumped.

Here are a few methods I thought about:

1, I could write a javascript helper function that loads partials through ajax into some form of local storage I suppose, and all subsequent templates that require that particular partial would first look inside local storage. I think this method isn't very safe because local storage isn't always guaranteed. And if I can't save them into local storage, partials would result in too many ajax calls.

2, I could put them all into script tags inside my main html file. This would work reasonably well, especially with head.js (to enable parallel loading of script tags), but still - I think each script tag is a separate call to the server right? That doesn't exactly improve the situation.

3, I could put all templates into a single script tag (or html I guess) and manually filter through some kind of delimiter...like: "#template1(blabla template1 string) #template2(blablabla template2 string) and put those strings into globals. This would result only into a single call to the server,开发者_运维问答 all the rest is done on the client.

Suggestions? I have looked at existing templating engines, but I can't really determine how they do it. The code is pretty complicated

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The approach I took to spec out template calls and on-demand loads for the spec/rewrite of jQuery templates is to pipeline it.

See section 9 of the (early) draft spec, and see the conformance suite tests at the bottom for an example of custom on-demand template loading (Testcase "Main calls and Loaded just in time!" is the relevant one).

The basic gist is that plugin loaders (written in JS) get to hook in between-parsing and compiling to inspect the parse tree. A plugin pass gets an object mapping template names to parse trees. If they see any partial template selectors (to use your parlance) they can try and load any unresolved templates using AJAX calls or file I/O on Node.js, and add the partials to the input object to cause the compiler to compile the just loaded partials along with the public templates.

Efficiency-wise, see the benchmarks. I'm in the process of migrating the code to github : https://github.com/mikesamuel/jquery-jquery-tmpl-proposal in case you want to collaborate.