From 7305a9eed3842d37663a5539ba2edab6a0d52e27 Mon Sep 17 00:00:00 2001
From: Angelika Tyborska <angelikatyborska@fastmail.com>
Date: Mon, 1 Mar 2021 09:26:29 +0100
Subject: [PATCH] [v3] Add prerequisites to Practice Exercises (#583)

Co-authored-by: Tim Austin <tim@neenjaw.com>
---
 .prettierignore                           |   11 +
 .prettierrc                               |   17 +
 config.json                               | 1831 ++++++++++++---------
 exercises/practice/zipper/lib/bin_tree.ex |    2 +-
 4 files changed, 1059 insertions(+), 802 deletions(-)
 create mode 100644 .prettierignore
 create mode 100644 .prettierrc

diff --git a/.prettierignore b/.prettierignore
new file mode 100644
index 0000000000..426829f770
--- /dev/null
+++ b/.prettierignore
@@ -0,0 +1,11 @@
+# IDE files
+.idea/
+.vscode/
+.vs/
+.ionide/
+
+# GitHub templates
+.github/ISSUE_TEMPLATE/**/*
+
+# Language docs files
+docs/**
\ No newline at end of file
diff --git a/.prettierrc b/.prettierrc
new file mode 100644
index 0000000000..d996376878
--- /dev/null
+++ b/.prettierrc
@@ -0,0 +1,17 @@
+{
+  "arrowParens": "always",
+  "bracketSpacing": true,
+  "embeddedLanguageFormatting": "auto",
+  "endOfLine": "auto",
+  "htmlWhitespaceSensitivity": "css",
+  "insertPragma": false,
+  "printWidth": 80,
+  "proseWrap": "preserve",
+  "quoteProps": "as-needed",
+  "semi": false,
+  "singleQuote": true,
+  "tabWidth": 2,
+  "trailingComma": "es5",
+  "useTabs": false,
+  "vueIndentScriptAndStyle": false
+}
diff --git a/config.json b/config.json
index ae505b7229..c1af08b2ee 100644
--- a/config.json
+++ b/config.json
@@ -34,9 +34,7 @@
         "slug": "lasagna",
         "name": "Lasagna",
         "uuid": "c29c6092-9d44-4f21-8138-b873384fd90b",
-        "concepts": [
-          "basics"
-        ],
+        "concepts": ["basics"],
         "prerequisites": [],
         "status": "beta"
       },
@@ -44,50 +42,32 @@
         "slug": "pacman-rules",
         "name": "Pacman Rules",
         "uuid": "5e743355-1ef3-4b5d-b59d-03bbc9697e6c",
-        "concepts": [
-          "booleans"
-        ],
-        "prerequisites": [
-          "basics"
-        ],
+        "concepts": ["booleans"],
+        "prerequisites": ["basics"],
         "status": "beta"
       },
       {
         "slug": "freelancer-rates",
         "name": "Freelancer Rates",
         "uuid": "fee79e03-1496-476f-964f-e60632cb13dc",
-        "concepts": [
-          "integers",
-          "floating-point-numbers"
-        ],
-        "prerequisites": [
-          "basics"
-        ],
+        "concepts": ["integers", "floating-point-numbers"],
+        "prerequisites": ["basics"],
         "status": "beta"
       },
       {
         "slug": "log-level",
         "name": "Log Level",
         "uuid": "b26a2f11-d80a-42b9-881a-3575a83ad211",
-        "concepts": [
-          "cond",
-          "atoms"
-        ],
-        "prerequisites": [
-          "booleans"
-        ],
+        "concepts": ["cond", "atoms"],
+        "prerequisites": ["booleans"],
         "status": "beta"
       },
       {
         "slug": "language-list",
         "name": "Language List",
         "uuid": "3c53b340-680e-45c1-8979-3d79b441a65e",
-        "concepts": [
-          "lists"
-        ],
-        "prerequisites": [
-          "booleans"
-        ],
+        "concepts": ["lists"],
+        "prerequisites": ["booleans"],
         "status": "beta"
       },
       {
@@ -99,32 +79,22 @@
           "guards",
           "default-arguments"
         ],
-        "prerequisites": [
-          "cond"
-        ],
+        "prerequisites": ["cond"],
         "status": "beta"
       },
       {
         "slug": "secrets",
         "name": "Secrets",
         "uuid": "1e3ceb20-715c-4157-9192-13284217affc",
-        "concepts": [
-          "anonymous-functions",
-          "bit-manipulation"
-        ],
-        "prerequisites": [
-          "basics"
-        ],
+        "concepts": ["anonymous-functions", "bit-manipulation"],
+        "prerequisites": ["basics"],
         "status": "beta"
       },
       {
         "slug": "kitchen-calculator",
         "name": "Kitchen Calculator",
         "uuid": "f729493d-2249-4c10-9c77-da907d10aae1",
-        "concepts": [
-          "tuples",
-          "pattern-matching"
-        ],
+        "concepts": ["tuples", "pattern-matching"],
         "prerequisites": [
           "atoms",
           "floating-point-numbers",
@@ -136,38 +106,23 @@
         "slug": "high-school-sweetheart",
         "name": "High School Sweetheart",
         "uuid": "335df1cf-6aba-4ab6-b5c3-b4305ade09a4",
-        "concepts": [
-          "strings",
-          "pipe-operator"
-        ],
-        "prerequisites": [
-          "lists",
-          "pattern-matching"
-        ],
+        "concepts": ["strings", "pipe-operator"],
+        "prerequisites": ["lists", "pattern-matching"],
         "status": "beta"
       },
       {
         "slug": "name-badge",
         "name": "Name Badge",
         "uuid": "b6ae6cb4-f908-436f-916c-fa847e4a82fb",
-        "concepts": [
-          "nil",
-          "if"
-        ],
-        "prerequisites": [
-          "strings",
-          "booleans"
-        ],
+        "concepts": ["nil", "if"],
+        "prerequisites": ["strings", "booleans"],
         "status": "beta"
       },
       {
         "slug": "high-score",
         "name": "High Score",
         "uuid": "e7f3ba2b-a380-45d3-a48d-7ef3dc318a31",
-        "concepts": [
-          "module-attributes-as-constants",
-          "maps"
-        ],
+        "concepts": ["module-attributes-as-constants", "maps"],
         "prerequisites": [
           "lists",
           "tuples",
@@ -180,9 +135,7 @@
         "slug": "bird-count",
         "name": "Bird Count",
         "uuid": "e17088c8-c40f-4d4c-b5dd-d32f62b8087b",
-        "concepts": [
-          "recursion"
-        ],
+        "concepts": ["recursion"],
         "prerequisites": [
           "lists",
           "pattern-matching",
@@ -195,70 +148,39 @@
         "slug": "german-sysadmin",
         "name": "German Sysadmin",
         "uuid": "45f3a08f-fe0f-4e3e-b325-47bad3c74ea4",
-        "concepts": [
-          "charlists",
-          "case"
-        ],
-        "prerequisites": [
-          "lists",
-          "recursion",
-          "pattern-matching",
-          "guards"
-        ],
+        "concepts": ["charlists", "case"],
+        "prerequisites": ["lists", "recursion", "pattern-matching", "guards"],
         "status": "beta"
       },
       {
         "slug": "basketball-website",
         "name": "Basketball Website",
         "uuid": "ba03df1d-20e4-4527-a8a7-afc97a834975",
-        "concepts": [
-          "access-behaviour"
-        ],
-        "prerequisites": [
-          "maps",
-          "strings",
-          "recursion",
-          "nil"
-        ],
+        "concepts": ["access-behaviour"],
+        "prerequisites": ["maps", "strings", "recursion", "nil"],
         "status": "beta"
       },
       {
         "slug": "file-sniffer",
         "name": "File Sniffer",
         "uuid": "1653d476-5354-4d99-a990-1db418a7281c",
-        "concepts": [
-          "binaries"
-        ],
-        "prerequisites": [
-          "strings",
-          "pattern-matching",
-          "if",
-          "bitstrings"
-        ],
+        "concepts": ["binaries"],
+        "prerequisites": ["strings", "pattern-matching", "if", "bitstrings"],
         "status": "beta"
       },
       {
         "slug": "dna-encoding",
         "name": "DNA Encoding",
         "uuid": "994c8760-8a58-4ef3-8a28-a0f9182f4d9f",
-        "concepts": [
-          "bitstrings",
-          "tail-call-recursion"
-        ],
-        "prerequisites": [
-          "charlists",
-          "recursion",
-          "pattern-matching"
-        ],
+        "concepts": ["bitstrings", "tail-call-recursion"],
+        "prerequisites": ["charlists", "recursion", "pattern-matching"],
         "status": "beta"
       },
       {
         "slug": "boutique-inventory",
         "name": "Boutique Inventory",
         "uuid": "be4ef2d1-2851-425d-9780-0326fbcb9845",
-        "concepts": [
-          "enum"
-        ],
+        "concepts": ["enum"],
         "prerequisites": [
           "lists",
           "maps",
@@ -273,24 +195,15 @@
         "slug": "rpn-calculator",
         "name": "RPN Calculator",
         "uuid": "f660a2e1-bb50-4626-8d3f-6cd7c44fa8db",
-        "concepts": [
-          "errors",
-          "try-rescue"
-        ],
-        "prerequisites": [
-          "anonymous-functions",
-          "pattern-matching",
-          "structs"
-        ],
+        "concepts": ["errors", "try-rescue"],
+        "prerequisites": ["anonymous-functions", "pattern-matching", "structs"],
         "status": "beta"
       },
       {
         "slug": "remote-control-car",
         "name": "Remote Control Car",
         "uuid": "d8d25b93-d918-421e-bb57-cbdaf428d9e2",
-        "concepts": [
-          "structs"
-        ],
+        "concepts": ["structs"],
         "prerequisites": [
           "maps",
           "multiple-clause-functions",
@@ -306,22 +219,15 @@
         "slug": "stack-underflow",
         "name": "Stack Underflow",
         "uuid": "9f698b46-fe8d-4641-a928-bcebfd9678df",
-        "concepts": [
-          "exceptions"
-        ],
-        "prerequisites": [
-          "access-behaviour",
-          "errors"
-        ],
+        "concepts": ["exceptions"],
+        "prerequisites": ["access-behaviour", "errors"],
         "status": "beta"
       },
       {
         "slug": "wine-cellar",
         "name": "Wine Cellar",
         "uuid": "921a03be-662a-4aea-b8fc-a87d199b1528",
-        "concepts": [
-          "keyword-lists"
-        ],
+        "concepts": ["keyword-lists"],
         "prerequisites": [
           "lists",
           "tuples",
@@ -335,125 +241,71 @@
         "slug": "rpn-calculator-output",
         "name": "RPN Calculator Output",
         "uuid": "68a8f721-5db4-4b31-95c8-fa6c38f64327",
-        "concepts": [
-          "try-rescue-else-after",
-          "dynamic-dispatch"
-        ],
-        "prerequisites": [
-          "file",
-          "try-rescue"
-        ],
+        "concepts": ["try-rescue-else-after", "dynamic-dispatch"],
+        "prerequisites": ["file", "try-rescue"],
         "status": "wip"
       },
       {
         "slug": "take-a-number",
         "name": "Take-A-Number",
         "uuid": "bec0b00f-816e-443a-af94-14ab4125e505",
-        "concepts": [
-          "processes",
-          "pids"
-        ],
-        "prerequisites": [
-          "atoms",
-          "recursion",
-          "pattern-matching",
-          "tuples"
-        ],
+        "concepts": ["processes", "pids"],
+        "prerequisites": ["atoms", "recursion", "pattern-matching", "tuples"],
         "status": "beta"
       },
       {
         "slug": "mensch-aergere-dich-nicht",
         "name": "Mensch Ärgere Dich Nicht",
         "uuid": "3e2f8bc6-20b4-4e8f-a658-9c270342208e",
-        "concepts": [
-          "streams"
-        ],
-        "prerequisites": [
-          "enum",
-          "tuples",
-          "if",
-          "ranges",
-          "randomness"
-        ],
+        "concepts": ["streams"],
+        "prerequisites": ["enum", "tuples", "if", "ranges", "randomness"],
         "status": "wip"
       },
       {
         "slug": "community-garden",
         "name": "Community Garden",
         "uuid": "1d6be9ec-5b5c-4c81-9bfa-2e3fc78c978f",
-        "concepts": [
-          "agent"
-        ],
-        "prerequisites": [
-          "processes",
-          "maps",
-          "structs"
-        ],
+        "concepts": ["agent"],
+        "prerequisites": ["processes", "maps", "structs"],
         "status": "beta"
       },
       {
         "slug": "date-parser",
         "name": "Date Parser",
         "uuid": "57198686-71c9-4f38-973a-a111435560e7",
-        "concepts": [
-          "regular-expressions"
-        ],
-        "prerequisites": [
-          "strings"
-        ],
+        "concepts": ["regular-expressions"],
+        "prerequisites": ["strings"],
         "status": "beta"
       },
       {
         "slug": "boutique-suggestions",
         "name": "Boutique Suggestions",
         "uuid": "f8208858-901e-4e5a-9f34-689bf8ad156c",
-        "concepts": [
-          "list-comprehensions"
-        ],
-        "prerequisites": [
-          "enum",
-          "lists",
-          "maps",
-          "keyword-lists",
-          "tuples"
-        ],
+        "concepts": ["list-comprehensions"],
+        "prerequisites": ["enum", "lists", "maps", "keyword-lists", "tuples"],
         "status": "beta"
       },
       {
         "slug": "bread-and-potions",
         "name": "Bread And Potions",
         "uuid": "a9fb9efa-ff37-4642-9118-c1351fd343ad",
-        "concepts": [
-          "protocols"
-        ],
-        "prerequisites": [
-          "structs",
-          "nil"
-        ],
+        "concepts": ["protocols"],
+        "prerequisites": ["structs", "nil"],
         "status": "beta"
       },
       {
         "slug": "rpg-character-sheet",
         "name": "RPG Character Sheet",
         "uuid": "83c31f5f-fc94-4315-9053-df5a5f5d5fb7",
-        "concepts": [
-          "io"
-        ],
-        "prerequisites": [
-          "strings",
-          "maps",
-          "atoms"
-        ],
+        "concepts": ["io"],
+        "prerequisites": ["strings", "maps", "atoms"],
         "status": "beta"
       },
       {
         "slug": "captains-log",
         "name": "Captain's Log",
         "uuid": "d805ae23-b5c9-494f-ab13-78a0e836391c",
-        "concepts": [
-          "erlang-libraries",
-          "randomness"
-        ],
+        "concepts": ["erlang-libraries", "randomness"],
         "prerequisites": [
           "enum",
           "ranges",
@@ -468,40 +320,23 @@
         "slug": "chessboard",
         "name": "Chessboard",
         "uuid": "6ea28f3e-a59a-45b0-83a7-38a2e96bdff7",
-        "concepts": [
-          "ranges"
-        ],
-        "prerequisites": [
-          "enum",
-          "integers",
-          "bitstrings",
-          "charlists"
-        ],
+        "concepts": ["ranges"],
+        "prerequisites": ["enum", "integers", "bitstrings", "charlists"],
         "status": "beta"
       },
       {
         "slug": "newsletter",
         "name": "Newsletter",
         "uuid": "5564c89c-4706-4a48-99a4-2ad26457f66f",
-        "concepts": [
-          "file"
-        ],
-        "prerequisites": [
-          "strings",
-          "enum",
-          "io",
-          "processes",
-          "pids"
-        ],
+        "concepts": ["file"],
+        "prerequisites": ["strings", "enum", "io", "processes", "pids"],
         "status": "beta"
       },
       {
         "slug": "library-fees",
         "name": "Library Fees",
         "uuid": "b5629003-638c-47c0-ad76-a0769f285053",
-        "concepts": [
-          "dates-and-time"
-        ],
+        "concepts": ["dates-and-time"],
         "prerequisites": [
           "integers",
           "floating-point-numbers",
@@ -518,453 +353,591 @@
         "name": "Hello World",
         "uuid": "cc96d65d-1c79-40d0-8fd2-9a6665a43b01",
         "prerequisites": [],
-        "difficulty": 1,
-        "topics": [
-          "strings"
-        ]
+        "practices": [],
+        "difficulty": 1
       },
       {
         "slug": "rna-transcription",
         "name": "RNA Transcription",
         "uuid": "a4629a60-752f-4234-99f1-6b3ac0b4ba18",
-        "prerequisites": [],
-        "difficulty": 2,
-        "topics": [
-          "strings"
-        ]
+        "prerequisites": [
+          "charlists",
+          "pattern-matching",
+          "multiple-clause-functions",
+          "case",
+          "enum"
+        ],
+        "practices": ["charlists", "enum"],
+        "difficulty": 2
       },
       {
         "slug": "word-count",
         "name": "Word Count",
         "uuid": "4a24ba2f-ae92-4095-be53-64bc881422ea",
-        "prerequisites": [],
-        "difficulty": 3,
-        "topics": [
-          "lists",
+        "prerequisites": [
+          "strings",
+          "regular-expressions",
+          "enum",
           "maps",
-          "reduce"
-        ]
+          "pipe-operator"
+        ],
+        "practices": ["strings", "regular-expressions", "pipe-operator"],
+        "difficulty": 3
       },
       {
         "slug": "roman-numerals",
         "name": "Roman Numerals",
         "uuid": "4c0ece49-5710-43a1-88b3-2fb149de8552",
-        "prerequisites": [],
-        "difficulty": 2,
-        "topics": [
-          "algorithms",
-          "pattern_matching"
-        ]
+        "prerequisites": [
+          "strings",
+          "recursion",
+          "guards",
+          "default-arguments",
+          "multiple-clause-functions",
+          "enum",
+          "maps",
+          "cond",
+          "case"
+        ],
+        "practices": ["recursion"],
+        "difficulty": 2
       },
       {
         "slug": "bob",
         "name": "Bob",
         "uuid": "d20b49dc-cb6d-45fc-a168-78d002072c75",
-        "prerequisites": [],
-        "difficulty": 2,
-        "topics": [
-          "control_flow",
-          "string_processing"
-        ]
+        "prerequisites": ["booleans", "strings", "regular-expressions", "cond"],
+        "practices": ["booleans", "strings", "cond"],
+        "difficulty": 3
       },
       {
         "slug": "beer-song",
         "name": "Beer Song",
         "uuid": "24db624b-7c80-409d-97d5-e1177f025c67",
-        "prerequisites": [],
-        "difficulty": 3,
-        "topics": [
-          "pattern_matching",
+        "prerequisites": [
+          "strings",
+          "multiple-clause-functions",
+          "default-arguments",
+          "ranges",
+          "enum",
           "recursion"
-        ]
+        ],
+        "practices": [
+          "multiple-clause-functions",
+          "default-arguments",
+          "strings"
+        ],
+        "difficulty": 3
       },
       {
         "slug": "robot-simulator",
         "name": "Robot Simulator",
         "uuid": "e5e55560-852f-4551-b4da-c9f4a3141470",
-        "prerequisites": [],
-        "difficulty": 6,
-        "topics": [
-          "pattern_matching",
-          "structs"
-        ]
+        "prerequisites": [
+          "atoms",
+          "multiple-clause-functions",
+          "guards",
+          "pattern-matching",
+          "case",
+          "strings",
+          "enum",
+          "structs",
+          "default-arguments"
+        ],
+        "practices": ["pattern-matching", "structs"],
+        "difficulty": 6
       },
       {
         "slug": "list-ops",
         "name": "List Ops",
         "uuid": "86658a31-d401-401b-80df-2c4df35f9b15",
-        "prerequisites": [],
-        "difficulty": 6,
-        "topics": [
-          "enumeration",
+        "prerequisites": [
           "lists",
-          "recursion"
-        ]
-      },
-      {
+          "recursion",
+          "tail-call-recursion",
+          "multiple-clause-functions",
+          "pattern-matching"
+        ],
+        "practices": ["lists", "recursion", "tail-call-recursion"],
+        "difficulty": 6
+      },
+      {
         "slug": "markdown",
         "name": "Markdown",
         "uuid": "5dfa24bf-e77c-47c6-88e1-e50cbeecd159",
-        "prerequisites": [],
-        "difficulty": 5,
-        "topics": [
-          "refactoring"
-        ]
+        "prerequisites": [
+          "strings",
+          "enum",
+          "recursion",
+          "regular-expressions",
+          "multiple-clause-functions",
+          "pattern-matching",
+          "cond",
+          "case",
+          "if"
+        ],
+        "practices": ["strings", "regular-expressions"],
+        "difficulty": 5
       },
       {
         "slug": "bank-account",
         "name": "Bank Account",
         "uuid": "5d5e0f6c-f4b7-418e-88f8-4b1d0f99bfb0",
-        "prerequisites": [],
-        "difficulty": 7,
-        "topics": [
-          "otp"
-        ]
+        "prerequisites": ["if", "processes", "pids", "agent"],
+        "practices": ["if", "processes", "pids", "agent"],
+        "difficulty": 7
       },
       {
         "slug": "zipper",
         "name": "Zipper",
         "uuid": "bc315734-051c-4735-9a8a-3aacb094d2ca",
-        "prerequisites": [],
-        "difficulty": 8,
-        "topics": [
-          "algorithms",
+        "prerequisites": [
           "recursion",
           "structs",
-          "trees"
-        ]
+          "protocols",
+          "if",
+          "nil",
+          "case",
+          "pattern-matching",
+          "multiple-clause-functions"
+        ],
+        "practices": ["structs", "recursion"],
+        "difficulty": 8
       },
       {
         "slug": "bowling",
         "name": "Bowling",
         "uuid": "3b252cc6-cc55-4187-891e-c10aaabac81f",
-        "prerequisites": [],
-        "difficulty": 8,
-        "topics": [
-          "algorithms",
-          "pattern_matching",
+        "prerequisites": [
+          "pattern-matching",
+          "multiple-clause-functions",
+          "guards",
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       {
         "slug": "two-fer",
         "name": "Two Fer",
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       {
         "slug": "nucleotide-count",
         "name": "Nucleotide Count",
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       {
         "slug": "pig-latin",
         "name": "Pig Latin",
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         "name": "Secret Handshake",
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-        "prerequisites": [],
-        "difficulty": 2,
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+          "bit-manipulation"
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         "slug": "space-age",
         "name": "Space Age",
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-        "prerequisites": [],
-        "difficulty": 2,
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+          "atoms",
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+          "pattern-matching",
+          "maps",
+          "module-attributes-as-constants"
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+          "module-attributes-as-constants"
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       {
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         "name": "Strain",
         "uuid": "d51edc8a-893b-4b05-912f-759e0d85123b",
-        "prerequisites": [],
-        "difficulty": 2,
-        "topics": [
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+        "prerequisites": [
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+          "lists",
+          "recursion",
+          "tail-call-recursion",
+          "cond",
+          "case",
+          "if"
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         "slug": "accumulate",
         "name": "Accumulate",
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-        "prerequisites": [],
-        "difficulty": 2,
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         "name": "Acronym",
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-        "prerequisites": [],
-        "difficulty": 2,
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         "slug": "raindrops",
         "name": "Raindrops",
         "uuid": "4522b139-6f0c-4172-a4fa-6a6adef33a9e",
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-        "difficulty": 2,
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         "name": "Run Length Encoding",
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-        "prerequisites": [],
-        "difficulty": 2,
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         "name": "Series",
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         "name": "DnD Character",
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-        "prerequisites": [],
-        "difficulty": 3,
-        "topics": [
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+          "randomness"
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       {
         "slug": "pangram",
         "name": "Pangram",
         "uuid": "20a0bbf8-751c-477a-a2cb-dd7cf4e4896c",
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-        "difficulty": 2,
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       {
         "slug": "scrabble-score",
         "name": "Scrabble Score",
         "uuid": "cc198564-72e6-444b-93b6-6b7ecf4d1759",
-        "prerequisites": [],
-        "difficulty": 2,
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       {
         "slug": "sum-of-multiples",
         "name": "Sum Of Multiples",
         "uuid": "5b8eece1-845f-4a5a-8a2f-fe2bf66f5e57",
-        "prerequisites": [],
-        "difficulty": 2,
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       {
         "slug": "grade-school",
         "name": "Grade School",
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-        "prerequisites": [],
-        "difficulty": 3,
-        "topics": [
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+        "practices": ["maps"],
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       },
       {
         "slug": "isogram",
         "name": "Isogram",
         "uuid": "55a20a0f-0131-4e4e-b14f-f3cb49e3cc04",
-        "prerequisites": [],
-        "difficulty": 3,
-        "topics": [
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-          "reduce"
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+        "prerequisites": ["strings", "enum", "regular-expressions"],
+        "practices": ["enum", "regular-expressions"],
+        "difficulty": 3
       },
       {
         "slug": "twelve-days",
         "name": "Twelve Days",
         "uuid": "9dfb5dfc-1123-492b-9383-2a4312c219a4",
-        "prerequisites": [],
-        "difficulty": 3,
-        "topics": [
-          "enumerations",
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+        "prerequisites": [
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+          "case",
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+          "recursion",
+          "maps",
+          "ranges"
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+        "practices": ["multiple-clause-functions", "strings", "recursion"],
+        "difficulty": 3
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       {
         "slug": "collatz-conjecture",
         "name": "Collatz Conjecture",
         "uuid": "01f7ce73-ad6a-42bb-a401-cbd485c081d4",
-        "prerequisites": [],
-        "difficulty": 2,
-        "topics": [
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+          "recursion",
+          "multiple-clause-functions",
+          "guards"
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       {
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         "name": "Sublist",
         "uuid": "146dd0ed-5210-4b3c-bb4b-8d0a8e832aab",
-        "prerequisites": [],
-        "difficulty": 2,
-        "topics": [
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+          "pattern-matching",
+          "recursion"
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       {
         "slug": "triangle",
         "name": "Triangle",
         "uuid": "546d92c7-c57b-4cbb-a721-9c393817a193",
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-        "difficulty": 2,
-        "topics": [
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+          "cond",
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       {
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         "name": "Flatten Array",
         "uuid": "0aae3af1-7c35-4d7c-aecf-8f89c7fbc300",
-        "prerequisites": [],
-        "difficulty": 3,
-        "topics": [
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           "lists",
-          "recursion"
-        ]
+          "recursion",
+          "multiple-clause-functions",
+          "pattern-matching",
+          "guards",
+          "nil"
+        ],
+        "practices": ["lists", "recursion", "nil"],
+        "difficulty": 3
       },
       {
         "slug": "matching-brackets",
         "name": "Matching Brackets",
         "uuid": "cf0084a0-7b1d-4714-b7b2-618e3ad6e147",
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-        "difficulty": 3,
-        "topics": [
-          "algorithms",
-          "enumeration",
-          "reduce"
-        ]
-      },
-      {
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+          "strings",
+          "regular-expressions",
+          "cond",
+          "case",
+          "if",
+          "recursion",
+          "enum",
+          "maps",
+          "pattern-matching",
+          "multiple-clause-functions",
+          "binaries"
+        ],
+        "practices": ["strings", "recursion", "pattern-matching"],
+        "difficulty": 3
+      },
+      {
         "slug": "anagram",
         "name": "Anagram",
         "uuid": "21e70267-097e-476f-aaff-233483514802",
-        "prerequisites": [],
-        "difficulty": 2,
-        "topics": [
-          "enumeration",
-          "filter"
-        ]
+        "prerequisites": ["strings", "enum"],
+        "practices": ["strings", "enum"],
+        "difficulty": 2
       },
       {
         "slug": "hamming",
         "name": "Hamming",
         "uuid": "aca03bcb-eb70-4646-be34-8c1a44026e9b",
-        "prerequisites": [],
-        "difficulty": 2,
-        "topics": [
-          "string_processing"
-        ]
+        "prerequisites": [
+          "atoms",
+          "tuples",
+          "charlists",
+          "multiple-clause-functions",
+          "guards",
+          "enum",
+          "recursion"
+        ],
+        "practices": ["enum", "recursion"],
+        "difficulty": 2
       },
       {
         "slug": "matrix",
         "name": "Matrix",
         "uuid": "f0df392c-8ace-4639-b555-5e61e54a854e",
-        "prerequisites": [],
-        "difficulty": 3,
-        "topics": [
-          "string_processing",
-          "structs"
-        ]
+        "prerequisites": ["strings", "enum", "structs", "tuples", "maps"],
+        "practices": ["strings", "enum", "structs", "tuples", "maps"],
+        "difficulty": 3
       },
       {
         "slug": "phone-number",
@@ -985,76 +958,117 @@
           "binaries"
         ],
         "practices": ["strings", "regular-expressions"],
-        "difficulty": 4,
-        "topics": [
-          "pattern_matching",
-          "string_processing"
-        ]
+        "difficulty": 4
       },
       {
         "slug": "say",
         "name": "Say",
         "uuid": "5ecbe1c9-12e3-42b6-921a-bc2d32011930",
-        "prerequisites": [],
-        "difficulty": 3,
-        "topics": [
-          "pattern_matching"
-        ]
+        "prerequisites": [
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+          "atoms",
+          "tuples",
+          "strings",
+          "multiple-clause-functions",
+          "case",
+          "guards",
+          "enum",
+          "recursion",
+          "maps",
+          "ranges",
+          "module-attributes-as-constants"
+        ],
+        "practices": ["guards", "maps", "module-attributes-as-constants"],
+        "difficulty": 3
       },
       {
         "slug": "nth-prime",
         "name": "Nth Prime",
         "uuid": "6d0c0785-3514-44fc-9b5a-0758989d1c6a",
-        "prerequisites": [],
-        "difficulty": 2,
-        "topics": [
-          "algorithms",
-          "math",
-          "recursion"
-        ]
+        "prerequisites": [
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+          "cond",
+          "case",
+          "if",
+          "enum",
+          "recursion",
+          "multiple-clause-functions",
+          "guards",
+          "ranges",
+          "streams",
+          "errors",
+          "exceptions"
+        ],
+        "practices": ["integers", "recursion", "ranges", "errors"],
+        "difficulty": 2
       },
       {
         "slug": "binary-search",
         "name": "Binary Search",
         "uuid": "89204af8-3914-404b-8984-39a8d60362c4",
-        "prerequisites": [],
-        "difficulty": 3,
-        "topics": [
-          "algorithms",
-          "recursion"
-        ]
+        "prerequisites": [
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+          "integers",
+          "recursion",
+          "multiple-clause-functions",
+          "guards",
+          "cond"
+        ],
+        "practices": ["tuples", "recursion", "cond"],
+        "difficulty": 3
       },
       {
         "slug": "isbn-verifier",
         "name": "ISBN Verifier",
         "uuid": "0fb09d01-1f8b-4654-9004-52baa057412e",
-        "prerequisites": [],
-        "difficulty": 3,
-        "topics": [
-          "string_processing"
-        ]
+        "prerequisites": [
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+          "regular-expressions",
+          "if",
+          "cond",
+          "case",
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+        ],
+        "practices": ["strings", "regular-expressions", "ranges"],
+        "difficulty": 3
       },
       {
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         "name": "Leap",
         "uuid": "3d0d82d7-fdff-4dd5-b720-7246317bb023",
-        "prerequisites": [],
-        "difficulty": 3,
-        "topics": [
-          "algorithms"
-        ]
+        "prerequisites": [
+          "integers",
+          "booleans",
+          "multiple-clause-functions",
+          "guards"
+        ],
+        "practices": [
+          "integers",
+          "booleans",
+          "multiple-clause-functions",
+          "guards"
+        ],
+        "difficulty": 3
       },
       {
         "slug": "tournament",
         "name": "Tournament",
         "uuid": "29a6f3f4-0d20-4447-8916-b98270780e0e",
-        "prerequisites": [],
-        "difficulty": 4,
-        "topics": [
-          "formatting",
-          "sorting",
-          "string_processing"
-        ]
+        "prerequisites": [
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+          "strings",
+          "maps",
+          "enum",
+          "multiple-clause-functions",
+          "pattern-matching",
+          "guards",
+          "cond",
+          "case",
+          "if"
+        ],
+        "practices": ["maps", "enum", "pattern-matching"],
+        "difficulty": 4
       },
       {
         "slug": "all-your-base",
@@ -1062,539 +1076,754 @@
         "uuid": "f71d5f38-fcc9-4044-ade9-f779a8686c69",
         "prerequisites": [
           "atoms",
-          "tuples"
+          "tuples",
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+          "pattern-matching",
+          "guards",
+          "cond",
+          "case",
+          "if",
+          "recursion",
+          "tail-call-recursion",
+          "enum"
+        ],
+        "practices": [
+          "integers",
+          "multiple-clause-functions",
+          "pattern-matching"
         ],
-        "difficulty": 2,
-        "topics": [
-          "math",
-          "numbers",
-          "translation"
-        ]
+        "difficulty": 2
       },
       {
         "slug": "binary-search-tree",
         "name": "Binary Search Tree",
         "uuid": "77fe5eb6-a35b-4af4-9512-275f140c25d6",
-        "prerequisites": [],
-        "difficulty": 3,
-        "topics": [
-          "algorithms",
-          "trees"
-        ]
+        "prerequisites": [
+          "multiple-clause-functions",
+          "pattern-matching",
+          "guards",
+          "cond",
+          "case",
+          "if",
+          "enum",
+          "maps",
+          "recursion",
+          "nil"
+        ],
+        "practices": ["maps", "recursion", "nil"],
+        "difficulty": 3
       },
       {
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         "name": "Grains",
         "uuid": "b030fa38-8935-4665-98c3-77f8434a6ea1",
-        "prerequisites": [],
-        "difficulty": 3,
-        "topics": [
-          "recursion",
-          "reduce"
-        ]
+        "prerequisites": [
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+          "enum",
+          "strings",
+          "regular-expressions",
+          "file"
+        ],
+        "practices": ["case", "strings", "regular-expressions", "file"],
+        "difficulty": 4
       },
       {
         "slug": "difference-of-squares",
         "name": "Difference Of Squares",
         "uuid": "bb9b24da-1ee6-42fb-936f-5fc41d97ee27",
-        "prerequisites": [],
-        "difficulty": 4,
-        "topics": [
-          "math",
-          "reduce"
-        ]
+        "prerequisites": ["integers", "enum", "ranges"],
+        "practices": ["enum", "ranges"],
+        "difficulty": 4
       },
       {
         "slug": "dominoes",
         "name": "Dominoes",
         "uuid": "9fdeb525-90d8-45ca-9a24-ca46b4363e03",
-        "prerequisites": [],
-        "difficulty": 4,
-        "topics": [
-          "algorithms",
-          "enumerations",
+        "prerequisites": [
+          "tuples",
+          "atoms",
+          "multiple-clause-functions",
+          "pattern-matching",
+          "guards",
+          "case",
+          "cond",
+          "if",
+          "enum",
           "recursion",
-          "sorting",
-          "trees"
-        ]
+          "tail-call-recursion"
+        ],
+        "practices": ["recursion", "tail-call-recursion"],
+        "difficulty": 4
       },
       {
         "slug": "alphametics",
         "name": "Alphametics",
         "uuid": "7ed99829-acd8-4724-b92f-85146f1709f9",
-        "prerequisites": [],
-        "difficulty": 5,
-        "topics": [
-          "algorithms",
-          "backtracking",
-          "strings"
-        ]
+        "prerequisites": [
+          "strings",
+          "regular-expressions",
+          "multiple-clause-functions",
+          "pattern-matching",
+          "guards",
+          "case",
+          "cond",
+          "if",
+          "enum",
+          "charlists",
+          "ranges"
+        ],
+        "practices": ["strings", "enum", "pattern-matching"],
+        "difficulty": 7
       },
       {
         "slug": "pythagorean-triplet",
         "name": "Pythagorean Triplet",
         "uuid": "087a2a3b-71e2-4473-ab2f-3be5240567b5",
-        "prerequisites": [
-          "task"
-        ],
-        "practices": [
-          "task"
-        ],
-        "difficulty": 5,
-        "topics": [
-          "algorithms",
-          "math",
-          "reduce"
-        ]
+        "prerequisites": ["integers", "ranges", "list-comprehensions", "task"],
+        "practices": ["list-comprehensions", "task"],
+        "difficulty": 5
       },
       {
         "slug": "wordy",
         "name": "Wordy",
         "uuid": "087940a2-5372-4ff3-aa9f-ce2eb982d91c",
-        "prerequisites": [],
-        "difficulty": 6,
-        "topics": [
-          "parsers"
-        ]
+        "prerequisites": [
+          "strings",
+          "regular-expressions",
+          "multiple-clause-functions",
+          "pattern-matching",
+          "guards",
+          "case",
+          "cond",
+          "if",
+          "enum",
+          "errors",
+          "exceptions"
+        ],
+        "practices": ["regular-expressions", "pattern-matching"],
+        "difficulty": 7
       },
       {
         "slug": "dot-dsl",
         "name": "Dot DSL",
         "uuid": "c316b8ef-7b2d-43d4-b402-f7d28b0cdaa7",
-        "prerequisites": [],
-        "difficulty": 8,
-        "topics": [
-          "graphs",
-          "structs"
-        ]
+        "prerequisites": [
+          "structs",
+          "regular-expressions",
+          "multiple-clause-functions",
+          "pattern-matching",
+          "guards",
+          "case",
+          "cond",
+          "if",
+          "enum",
+          "errors",
+          "exceptions",
+          "keyword-lists",
+          "nil",
+          "macros"
+        ],
+        "practices": ["keyword-lists", "structs", "macros"],
+        "difficulty": 8
       }
     ],
-    "foregone": [
-      "robot-name"
-    ]
+    "foregone": ["robot-name"]
   },
   "concepts": [
     {
diff --git a/exercises/practice/zipper/lib/bin_tree.ex b/exercises/practice/zipper/lib/bin_tree.ex
index 1366224bbf..e2d681e891 100644
--- a/exercises/practice/zipper/lib/bin_tree.ex
+++ b/exercises/practice/zipper/lib/bin_tree.ex
@@ -18,7 +18,7 @@ defimpl Inspect, for: BinTree do
   # A custom inspect instance purely for the tests, this makes error messages
   # much more readable.
   #
-  # BinTree[value: 3, left: BinTree[value: 5, right: BinTree[value: 6]]] becomes (3:(5::(6::)):)
+  # %BinTree{value: 3, left: %BinTree{value: 5, right: %BinTree{value: 6}}} becomes (3:(5::(6::)):)
   def inspect(%BinTree{value: value, left: left, right: right}, opts) do
     concat([
       "(",