partial-function SKILL.md skillA

partial-function from ncaq/konoka is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.

Install it, pinned
mdr add ncaq/konoka/partial-function@git:20260521.b4f4c8e

Pins git:20260521.b4f4c8e in mdr.lock. Pin the fingerprint instead.

Audit grade
A, 17 of 17 checks passed
Kind
SKILL.md skill
Repository
ncaq/konoka
Path
plugins/haskell-tasuke/skills/partial-function/SKILL.md
Versions recorded
1
Latest version
git:20260521.b4f4c8e, committed May 21, 2026
Size
2,680 bytes
Repository stars
3
License
Apache-2.0

Avoid partial functions such as head, fromJust, read, and (!!) in Haskell. Prefer total functions, Maybe-returning variants, and other safe alternatives. Use when writing or reviewing Haskell code that accesses lists, parses strings, or handles Maybe.

Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.

What the file says

# 部分関数の禁止

純粋関数であるにもかかわらず、
特定の入力に対して例外を投げる部分関数の使用は禁止します。

部分関数は型の上ではすべての入力を受け付けるように見えますが、
実際には一部の入力でしか正しく動作しません。
そのため型検査を通過しても実行時にクラッシュする原因になります。

純粋関数空間では安全な方法では例外を捕捉することが出来ないため、
エラーの処理が困難になります。

遅延評価と組み合わせると、
例外が発生するタイミングが予測できなくなり、
例外を捕捉しているはずなのに別の場所で評価された時に例外が発生することもあります。

全域関数や、
失敗を`Maybe`や`Either`などで返す関数に置き換えてください。

## 代表的な部分関数と代替

### fromJust

`Maybe`の中身を取り出しますが、
`Nothing`に対しては例外を投げます。

`fromMaybe`でデフォルト値を与えるか、
`maybe`やパターンマッチで`Nothing`の場合を明示的に処理してください。

### read

文字列をパースしますが、
失敗すると例外を投げます。

`readMaybe`や、
導入されていれば`readMay`を使い、
失敗を`Maybe`として受け取ってください。

### head / tail / init / last

空リストに対して例外を投げます。

先頭要素が欲しいだけなら`listToMaybe`やパターンマッチを使ってください。

導入されていれば`headMay`などの`Maybe`を返すバージョンを使ってください。

空でないことが事前条件であるなら、
`NonEmpty`で型として表現すれば、
`NonEmpty.head`は全域関数になります。

### (!!)

範囲外のインデックスに対して例外を投げます。

`Data.List.(!?)`のように、
`Maybe`を返す添字アクセスを使ってください。

そもそもリストの添字アクセスはパフォーマンスが悪いので、
可能な限り走査するようなコードを書いてください。

### maximum / minimum / foldr1 / foldl1

空のコンテナに対して例外を投げます。

`NonEmpty`版を使うか、
初期値を与える安全なバージョンを使ってください。

Read the whole file at its exact version.

How to install

The exact contents, by fingerprint
mdr add ncaq/konoka/partial-function@sha256:8cf70d05ac2ad762

The line at the top of this page pins the label git:20260521.b4f4c8e, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.

Badge

mdr badge

[![mdr](https://markdownregistry.com/badge/art_uvndbpqgjwkh7grf.svg)](https://markdownregistry.com/a/art_uvndbpqgjwkh7grf)

2 badge image fetches in 30 days. What the badge shows.

Versions

The registry has recorded 1 version of this file, committed on May 21, 2026.

versioncommittedcommitsizeaudit
git:20260521.b4f4c8e latest2026-05-21 b4f4c8e 2,680 BA view

Audit of the latest version

A  17 of 17 checks passed. Fixed automatic checks with no AI involved, so the same checks give the same answer every run.
  • pass: Frontmatter block present
  • pass: Frontmatter declares a name
  • pass: Frontmatter declares a description
  • pass: Size between 200 bytes and 200 KB (2680 bytes)
  • pass: No zero-width or bidi control characters
  • pass: No instruction hidden inside an HTML comment
  • pass: No link to an exfiltration or paste host
  • pass: No credential-shaped string
  • pass: No instruction to send local credentials anywhere
  • pass: No text hidden with inline styles
  • pass: No prompt-injection phrasing
  • pass: No curl or wget piped into a shell
  • pass: No recursive delete of root, home or parent
  • pass: No instruction to read or print local credentials
  • pass: No base64 blob over 200 characters
  • pass: No link to a raw IP address
  • pass: No script tag

Source

GitHub

ncaq/konoka · 3 stars · license Apache-2.0 · pushed 2026-10-19 · branch master

API

GET https://markdownregistry.com/api/v1/artifacts/art_uvndbpqgjwkh7grf
GET https://markdownregistry.com/api/v1/resolve?ref=ncaq/konoka/partial-function
GET https://markdownregistry.com/api/v1/blob/8cf70d05ac2ad762ddc57227892134e8102225c96fa877cc78ff3ece37fd7cd8

Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.

Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.

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