Add articles documentation

building/config.json

@@ -562,6 +562,13 @@
     "title": "Approaches",
     "blurb": "Learn how to write approaches for exercises"
   },
+  {
+    "uuid": "362853a0-dc4a-43ee-abbb-d4a14cb5b5bb",
+    "slug": "tracks/articles",
+    "path": "building/tracks/articles.md",
+    "title": "Articles",
+    "blurb": "Learn how to write articles for exercises"
+  },
   {
     "uuid": "8db530bb-e11b-4497-b088-5b4c997e09a2",
     "slug": "tracks/presentation",

building/configlet/lint.md

@@ -322,6 +322,102 @@ The `config.json` file should have the following checks:
 - The `"test_runner"` key is optional
 - The `"test_runner"` value must be a boolean
 
+### Rule: exercises/{concept|practice}/<slug>/.approaches/config.json is valid
+
+- The file's presence is optional, unless there is a `introduction.md` or a sibling directory
+- The file must be valid JSON
+- The JSON root must be an object
+- The `"introduction.authors"` key is optional
+- The `"introduction.authors"` value must be an array
+- The `"introduction.authors"` values must be non-blank strings¹
+- The `"introduction.authors"` values must not have duplicates
+- The `"introduction.authors"` values are treated case-insensitively
+- If the `"introduction.authors"` array is non-empty, there must be a non-empty `introduction.md` file
+- The `"introduction.contributors"` key is optional
+- The `"introduction.contributors"` value must be an array
+- The `"introduction.contributors"` values must be non-blank strings¹
+- The `"introduction.contributors"` values must not have duplicates
+- The `"introduction.contributors"` values are treated case-insensitively
+- If the `"introduction.contributors"` array is non-empty, there must be a non-empty `introduction.md` file
+- Users can only be listed in either the `"introduction.authors"` or `"introduction.contributors"` array (no overlap)
+- The `"approaches"` key is optional, unless there is a sibling directory present (which contains the approach' files)
+- The `"approaches"` value must be an array of objects
+- The `"approaches[].uuid"` key is required
+- The `"approaches[].uuid"` value must be a unique version 4 UUID string⁶
+- The `"approaches[].uuid"` value for each concept must never change
+- The `"approaches[].slug"` key is required
+- The `"approaches[].slug"` value must be a kebab-case string² with length <= 255
+- The `"approaches[].slug"` value must have a corresponding non-empty `<slug>/content.md` file
+- The `"approaches[].slug"` value must have a corresponding non-empty `<slug>/snippet.txt` file
+- The `"approaches[].name"` key is required
+- The `"approaches[].name"` value must be a Title Case string³ with length <= 255
+- The `"approaches[].blurb"` key is required
+- The `"approaches[].blurb"` value must be a non-blank string¹ with length <= 350
+- The `"approaches[].authors"` key is required
+- The `"approaches[].authors"` value must be a non-empty array
+- The `"approaches[].authors"` values must be non-blank strings¹
+- The `"approaches[].authors"` values must not have duplicates
+- The `"approaches[].authors"` values are treated case-insensitively
+- The `"approaches[].contributors"` key is optional
+- The `"approaches[].contributors"` value must be an array
+- The `"approaches[].contributors"` values must be non-blank strings¹
+- The `"approaches[].contributors"` values must not have duplicates
+- The `"approaches[].contributors"` values are treated case-insensitively
+- Users can only be listed in either the `"approaches[].authors"` or `"approaches[].contributors"` array (no overlap)
+
+### Rule: exercises/{concept|practice}/&lt;slug&gt;/.approaches/&lt;approach-slug&gt;/content.md is valid
+
+- The file's presence is required if a matching `"approaches[].slug"` entry exists in the `.approaches/config.json` file
+- The Markdown must conform to the [Markdown standards](/docs/building/markdown/markdown)
+- Links must be absolute (relative links are not allowed)
+
+### Rule: exercises/{concept|practice}/&lt;slug&gt;/.approaches/&lt;approach-slug&gt;/snippet.txt is valid
+
+- The file's presence is required if a matching `"approaches[].slug"` entry exists in the `.approaches/config.json` file
+- The snippet must have at most 8 lines
+
+### Rule: exercises/{concept|practice}/&lt;slug&gt;/.articles/config.json is valid
+
+- The file's presence is optional, unless there is a sibling directory
+- The file must be valid JSON
+- The JSON root must be an object
+- The `"articles"` key is optional, unless there is a sibling directory present (which contains the article' files)
+- The `"articles"` value must be an array of objects
+- The `"articles[].uuid"` key is required
+- The `"articles[].uuid"` value must be a unique version 4 UUID string⁶
+- The `"articles[].uuid"` value for each concept must never change
+- The `"articles[].slug"` key is required
+- The `"articles[].slug"` value must be a kebab-case string² with length <= 255
+- The `"articles[].slug"` value must have a corresponding non-empty `<slug>/content.md` file
+- The `"articles[].slug"` value must have a corresponding non-empty `<slug>/snippet.md` file
+- The `"articles[].name"` key is required
+- The `"articles[].name"` value must be a Title Case string³ with length <= 255
+- The `"articles[].blurb"` key is required
+- The `"articles[].blurb"` value must be a non-blank string¹ with length <= 350
+- The `"articles[].authors"` key is required
+- The `"articles[].authors"` value must be a non-empty array
+- The `"articles[].authors"` values must be non-blank strings¹
+- The `"articles[].authors"` values must not have duplicates
+- The `"articles[].authors"` values are treated case-insensitively
+- The `"articles[].contributors"` key is optional
+- The `"articles[].contributors"` value must be an array
+- The `"articles[].contributors"` values must be non-blank strings¹
+- The `"articles[].contributors"` values must not have duplicates
+- The `"articles[].contributors"` values are treated case-insensitively
+- Users can only be listed in either the `"articles[].authors"` or `"articles[].contributors"` array (no overlap)
+
+### Rule: exercises/{concept|practice}/&lt;slug&gt;/.articles/&lt;article-slug&gt;/content.md is valid
+
+- The file's presence is required if a matching `"articles[].slug"` entry exists in the `.articles/config.json` file
+- The Markdown must conform to the [Markdown standards](/docs/building/markdown/markdown)
+- Links must be absolute (relative links are not allowed)
+
+### Rule: exercises/{concept|practice}/&lt;slug&gt;/.articles/&lt;article-slug&gt;/snippet.md is valid
+
+- The file's presence is required if a matching `"articles[].slug"` entry exists in the `.articles/config.json` file
+- The Markdown must conform to the [Markdown standards](/docs/building/markdown/markdown)
+- The snippet must have at most 8 lines (leading and trailing code fence markers are ignored)
+
 ### Rule: exercises/shared/.docs/debug.md is valid
 
 - The file's presence is optional

building/tracks/README.md

@@ -20,8 +20,13 @@ Tracks have two types of exercises:
 - Concept exercises: they are designed to teach one or more concepts to a student. Check the [documentation](/docs/building/tracks/concept-exercises) for more information.
 - Practice exercises: they are designed to practice learned concepts. Check the [documentation](/docs/building/tracks/practice-exercises) for more information.
 
-Exercises can have approaches associated with them, which describe the different ways in which an exercise can be solved.
-Check the [documentation](/docs/building/tracks/approaches) for more information.
+### Dig deeper
+
+Each exercise has an optional Dig Deeper section that can contain:
+
+- [Approaches](/docs/building/tracks/approaches): different ways in which the exercise can be solved
+- [Articles](/docs/building/tracks/articles): describe interesting aspects of the exercise
+- Community videos: videos that showcase the exercise, usually by having someone solve the exercise from scratch
 
 ## Shared files
 

building/tracks/approaches.md

@@ -9,14 +9,15 @@ An approach should explore how an exercise can be solved a certain way.
 - Its contents should either:
   - Explore an idiomatic approach
   - Explore a non-idiomatic, but interesting approach
-  - Contain a meta discussion (e.g. comparing the performance of approaches)
 - Start with a (full) code sample
   - Liberally use code samples in the rest of the document
 - Feel free to dig deep into the topic
 - Link to useful resources (e.g. documentation)
 - The snippet should showcase the core of the approach
   - A maximum of 8 lines can be used
 
+If you'd like to compare different approaches, please write an [articles](/docs/building/tracks/articles).
+
 ## Approaches overview
 
 - Give context to the problem

building/tracks/articles.md

@@ -0,0 +1,19 @@
+# Articles
+
+Each exercise can have articles associated with them, which explore some interesting aspect of the exercise.
+
+## Topics
+
+Potential topics an article could explore:
+
+- Comparing the performance of different approaches
+- Anything interesting you can come up with!
+
+## General considerations
+
+- If your article is based on some code you've written, consider committing that code (within the article directory)
+  - An example being an article on performance, for which benchmarking code was written
+
+## What exercises to write articles for?
+
+Any exercise, as long as there is something interesting to explore.

building/tracks/concept-exercises.md

@@ -56,6 +56,14 @@ These files describe approaches for the exercise.
 - `.approaches/<approach-slug>/content.md`: description of the approach (optional)
 - `.approaches/<approach-slug>/snippet.txt`: snippet showcasing the approach (optional)
 
+### Article files
+
+These files describe articles for the exercise.
+
+- `.articles/config.json`: metadata for the articles (optional)
+- `.articles/<article-slug>/content.md`: description of the article (optional)
+- `.articles/<article-slug>/snippet.md`: snippet showcasing the article (optional)
+
 ### Exercise files
 
 The language-specific files, like the implementation and test files. The names of these files are track-specific.
@@ -72,11 +80,16 @@ exercises
 └── concept
     └── cars-assemble
         ├── .approaches
-        |   ├── performance (approach)
+        |   ├── for-loop
         |   |   ├── content.md
         |   |   └── snippet.txt
         |   ├── config.json
         |   └── introduction.md
+        ├── .articles
+        |   ├── performance
+        |   |   ├── content.md
+        |   |   └── snippet.md
+        |   └── config.json
         ├── .docs
         |   ├── introduction.md
         |   ├── instructions.md
@@ -403,7 +416,7 @@ If readability is your primary concern (and it usually should be), the LINQ-base
 
 **Presence:** Optional (required when an approach introduction or approach exists)
 
-This file contains meta information on the exercise:
+This file contains meta information on the exercise's approaches:
 
 - `introduction`: The GitHub username(s) of the exercise approach introduction's author(s) (optional)
 
@@ -432,6 +445,96 @@ This file contains meta information on the exercise:
   "approaches": [
     {
       "uuid": "448fb2b4-18ab-4e55-aa54-ad4ed6d5f7f6",
+      "slug": "span",
+      "title": "Use Span<T>",
+      "blurb": "Use Span<T> to efficiently reverse a string.",
+      "authors": ["erikschierboom"]
+    }
+  ]
+}
+```
+
+---
+
+### File: `.approaches/<approach-slug>/content.md`
+
+**Purpose:** Detailed description of the approach
+
+**Presence:** Optional (required for approaches)
+
+This file contains a detailed description of the approach.
+Check the [documentation](/docs/building/tracks/approaches) for more information on what should go in this file.
+
+#### Example
+
+````markdown
+# Span
+
+```csharp
+Span<char> chars = stackalloc char[input.Length];
+for (var i = 0; i < input.Length; i++)
+{
+    chars[input.Length - 1 - i] = input[i];
+}
+return new string(chars);
+```
+
+This `Span<T>` approach uses a `for` loop.
+````
+
+---
+
+### File: `.approaches/<approach-slug>/snippet.txt`
+
+**Purpose:** Snippet showcasing the approach
+
+**Presence:** Optional (required for approaches)
+
+This file contains a small snippet that showcases the approach.
+The snippet is shown on an exercise's dig deeper page.
+
+Its number of lines must be <= 8.
+
+Check the [documentation](/docs/building/tracks/approaches) for more information on what should go in this file.
+
+#### Example
+
+```csharp
+Span<char> chars = stackalloc char[input.Length];
+for (var i = 0; i < input.Length; i++)
+{
+    chars[input.Length - 1 - i] = input[i];
+}
+return new string(chars);
+```
+
+---
+
+### File: `.article/config.json`
+
+**Purpose:** Metadata for the articles
+
+**Presence:** Optional (required when an article exists)
+
+This file contains meta information on the exercise's articles:
+
+- `articles`: An array listing the detailed articles (optional)
+  - `uuid`: a V4 UUID that uniquely identifies the article. The UUID must be unique both within the track as well as across all tracks, and must never change
+  - `slug`: the article's slug, which is a lowercased, kebab-case string. The slug must be unique across all article slugs within the track. Its length must be <= 255.
+  - `title`: the article's title. Its length must be <= 255.
+  - `blurb`: A short description of this article. Its length must be <= 350. Markdown is _not_ supported (required)
+  - `authors`: The GitHub username(s) of the exercise article's author(s) (required)
+    - Including reviewers if their reviews substantially change the exercise article (to the extent where it feels like "you got there together")
+  - `contributors`: The GitHub username(s) of the exercise article's contributor(s) (optional)
+    - Including reviewers if their reviews are meaningful/actionable/actioned.
+
+#### Example
+
+```json
+{
+  "articles": [
+    {
+      "uuid": "6db71962-62d5-448b-a980-c20ae41013ed",
       "slug": "performance",
       "title": "Optimizing performance",
       "blurb": "Explore how to most efficiently reverse a string and what the trade-offs are.",
@@ -443,14 +546,14 @@ This file contains meta information on the exercise:
 
 ---
 
-### File: `.approaches/<approach-slug>/content.md`
+### File: `.articles/<article-slug>/content.md`
 
 **Purpose:** Detailed description of the approach
 
 **Presence:** Optional (required for approaches)
 
 This file contains a detailed description of the approach.
-Check the [documentation](/docs/building/tracks/approaches) for more information on what should go in this file.
+Check the [documentation](/docs/building/tracks/articles) for more information on what should go in this file.
 
 #### Example
 
@@ -469,26 +572,26 @@ In this document, we'll find out which approach is the most performant one.
 
 ---
 
-### File: `.approaches/<approach-slug>/snippet.txt`
+### File: `.articles/<article-slug>/snippet.txt`
 
 **Purpose:** Snippet showcasing the approach
 
-**Presence:** Optional (required for approaches)
+**Presence:** Optional (required for articles)
 
-This file contains a small snippet that showcases the approach.
-The snippet is shown on an exercise's approaches overview page.
+This file contains a small snippet that showcases the article.
+The snippet is shown on an exercise's dig deeper page.
 
 Its number of lines must be <= 8.
 
+Check the [documentation](/docs/building/tracks/articles) for more information on what should go in this file.
+
 #### Example
 
-```csharp
-Span<char> chars = stackalloc char[input.Length];
-for (var i = 0; i < input.Length; i++)
-{
-    chars[input.Length - 1 - i] = input[i];
-}
-return new string(chars);
+```markdown
+| Method |      Mean | Allocated |
+| -----: | --------: | --------: |
+|   Linq | 29.133 ns |      80 B |
+|  Array |  4.806 ns |         - |
 ```
 
 ---