Parametered partials hogan

[e2tha-e]

Addresses pattern-lab/patternlab-node#250

Summary of changes:

• Replace Mustache with Hogan for performance benefits
• patternMatcher must work with .extendedTemplate and not .template for recursive parametered partials to work
• new functions to register and preprocess partials
• paramToJson copied from main patternlab-node repo - its purpose it specific to pl's Mustache syntax

[geoffp]

Shouldn't these two be dependencies rather than devDependencies?

[geoffp]

Ah! They are. The diff misled me. :)

[geoffp]

Good catch on using .extendedTemplate.

Would you please:

1. Provide an example of the syntax that all this added machinery is intended to support, and
2. Give me rundown of the new partial registration process and why it's needed

[e2tha-e]

@geoffp
I've added JSDocs to try and explain item 2.
As for item 1:

• registerPartial is used in addPattern in pattern_assember.js
  • https://github.com/pattern-lab/patternlab-node/pull/416/files#diff-1fdc38d32c671a4eef4497b2d6ac9ec2R119
• preprocessPartials is used in preprocessPatternlabPartials in patternlab.js
  • https://github.com/pattern-lab/patternlab-node/pull/416/files#diff-d4659ef22e1b32c5b35db4af8c3218aeR90

[e2tha-e]

FYI, neither Mustache nor Hogan has a native registerPartial method. Handlebars, and probably many other "more powerful" templating languages do have this method. I'm just applying an already existing convention to Hogan.

[geoffp]

I'm trying to read the big PR that you linked to, but I only have so much time in a day for code review and I just can't get through it all in one sitting or even two. I also still don't have an example of the syntax you're trying to support.

Having worked extensively on pattern parameters and style modifiers, how possible do you think it would be to move most of the machinery of dealing with them into the Mustache engine itself? They're not wanted or needed for other engines, and it adds a huge amount of complexity to the main app.

[e2tha-e]

In the links I provided, I highlighted the lines where registerPartial and preprocessPartials are called. Here they are out of context:

pattern.registerPartial(patternlab);

engine.preprocessPartials(pattern_assembler, patternlab);

Maybe I'm not fully understanding what sort of example or explanation you want. Please do ask for more specifics if you want.

I'll definitely give the proposal to make my changes Mustache-specific some thought. But in actuality, I think my changes are simplifying the main app, especially in regards to partial inclusion. If you look at the code statistics for pattern-lab/patternlab-node/pull/416 , I reduced the amount of code by 72 lines. I'm obviously more than compensating by increasing the amount of code in patternengine-node-mustache, but that's Mustache-specific. I tested my changes to the main app with the Handlebars engine, and it worked perfectly, with just a minor pr to patternengine-node-handlebars.

[bmuenzenmeyer]

Please see pattern-lab/patternlab-node#603 for an explanation of why I am closing this PR.