Faster pattern preprocessing

[tburny]

I am using Pattern Lab Node v4.7.2 on Linux, with Node v4.7.0, using the Grunt Edition.
In Spirit of #316

Currently the processPatternsIterative and processPatternsRecursive methods in patternlab.js take a long time (in terms of magnitudes 10 seconds), especially for large pattern trees with lots of data.

We should therefor collect ideas how to improve this step.

• Extend incremental builds to skip processing unchanged patterns?
• Cache pattern lookups and use ES6 Map for this. This potentially prevents falling back to the file system every time a pattern is looked up.
• your suggestion here

[bmuenzenmeyer]

Anything we do needs to incorporate all of the async work @geoffp is doing. I suggest we merge dev into his branches asap. This will be a priority of mine. I know there are some PRs out there to this effect.

[geoffp]

@bmuenzenmeyer, @tburny, see #562 (comment)

[bmuenzenmeyer]

unassigning myself - i only like to assign issues to things i plan to work on imminently

[bmuenzenmeyer]

Curious if https://github.com/pattern-lab/patternlab-node/releases/tag/v2.9.0 handled the majority of concerns. this issue is a bit to vague right now, but is good in an aspirational sense.

for clarity's sake, i am removing from the 3.0 milestone

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.