critical comments on patterns and template

[publicsphere]

Looking at the elements in the README it states that "A pattern language is a collection of patterns, which share a pattern template." I don't know how to get out of this exactly but elements of a pattern language do not have to share the same pattern template. This is one of the main objectives of the rework.

I thought we agreed that a pattern language was a collection of patterns — or, at least, we were using that terminology.

Also, in my view, I would rewrite "A pattern has an associated pattern template that defines what features it may have." as "A pattern has associated pattern templates that defines what features it may have, depending on context."

A pattern "template" can be defined as any set of pattern features (it seems to me). For example, the following sets could serve as "templates" in various LV pattern uses:

set of ALL the features used in LV patterns
set of the features used in LV on labs front page
set of the features used in LV in AM app
set of the features used in LV in current PS usage
set of the features used in LV on greengeeks pages
set of the features used in LV for cards

[smrose]

I've removed the restriction that members of a pattern language must share a template. Now, a pattern language is a collection of any defined patterns.

[smrose]

We have the concept of a "pattern view," which is distinct from that of a "pattern template." A pattern template is a set of all the pattern features that a pattern may or must have. A pattern view describes how a subset of those features are used to create a view of the pattern - as such, it has a name and a "layout," where the layout is essentially an HTML file in which features are referenced via tokens. At display time, feature values replace the tokens to create a per-pattern HTML file.

Each pattern is tied to a pattern template, as is each pattern view. But pattern languages are not. In order to be able to display all the patterns in a pattern language, there must be a pattern view selected for each pattern template that participates. This is easy to see on the pattern display page, which presents a list of all the patterns in the selected language and the ability to choose a view for each participating template. When a view has been selected for a template, patterns using that template become available for display. In the event that there is only a single view defined for a template, there is no choice to be made and those patterns are immediately available for display. In the even that there are no views defined for a template, there is no way to display those patterns and a warning to that effect is displayed.