Modules

Version 0: expect changes

While the crate is at version 0.x:

• The split into modules, and so into Cargo features, may change. A helper can move to another module — and so to another feature to enable — from one release to the next.
• The code and security verification will keep improving. More checks (fuzzing and static analysis, for instance) are planned, and each helper’s page says what it guarantees and what it does not.

Pin the exact version and read the changelog before upgrading.

The helpers4 crate is organised in 34 modules. Each module is a Cargo feature of the same name, and all of them are enabled by default (cargo add helpers4).

A helper that needs a dependency the rest of its module does without sits behind an opt-in sub-feature named <module>-<what> (listed after its module below), so the default features stay dependency-free.

Install only what you use

Turn the default features off and name the modules you want:

cargo add helpers4 --no-default-features --features string,hex

or in Cargo.toml:

[dependencies]
helpers4 = { version = "0.0.11", default-features = false, features = ["string", "hex"] }

Modules

Module	Cargo feature	What it covers	Items
animation	animation	Animation timing without a framework: Easing curves (the CSS keywords, cubic-bezier(), steps() and linear(), read from a CSS string or built directly), physical Springs with their settling time, and to_css_linear to turn any curve into a CSS linear().	5
ansi	ansi	ANSI escape sequences: remove them from captured output and build styled text.	5
array	array	Helpers for slices and Vecs that the standard library does not provide.	16
bytes	bytes	Helpers for byte slices and sizes that the standard library does not provide.	15
cache	cache	Caches and stores: entries that expire with a passed-in clock (ExpiringMap), and a capacity-bounded map that evicts by recency instead (LruCache).	3
ci	ci	Detecting CI environments and reporting pipeline status.	7
color	color	Colors without a dependency: parsing, hex, CSS output, HSL, alpha, blending and WCAG contrast.	12
commit	commit	Conventional Commits: parse a message, decide the version bump, validate.	6
date	date	Calendar dates without time zones: validation, ISO 8601 text, weekdays and day arithmetic.	5
duration	duration	Parsing and formatting of durations as short human-readable strings (1h30m).	3
env	env	Dotenv (.env) helpers working on plain text: no file or process-environment access, so they are deterministic and easy to test.	9
font	font	Fonts without a dependency: CSS font matching, the names design tools give to weights and styles, and reading a font file’s names, weight and style.	14
fs	fs	File-system helpers: safe writes, missing-file-as-None, listing and path checks.	5
function	function	Helpers around functions: composition, memoization, retrying and rate limiting.	6
future	future	Runtime-neutral helpers for Futures, built on the standard library only.	5
geometry	geometry	2D geometry in f64: Point, Rect and the affine Matrix, in the layout of CSS and SVG matrix(a b c d e f).	15
hex	hex	Byte/text encodings with typed errors: hexadecimal, and base64/base32 (RFC 4648).	12
http	http	HTTP header value helpers on plain text: no dependency on an HTTP crate.	1
id	id	Unique identifiers without the uuid or ulid crates: Uuid (v4 random, v7 sortable by time), Ulid, and short URL-safe ids over an Alphabet.	8
iter	iter	Helpers for any Iterator, not only slices: work on a lazy, single-use or unbounded source.	3
kiwi	kiwi	Decoding of the Kiwi binary format, Evan Wallace’s schema-based serialization (used by Figma’s .fig files, but generic).	7
license	license	SPDX license identifiers and expressions: look a license up, parse MIT OR Apache-2.0, check it against a policy, write a source header.	7
map	map	Helpers for HashMap that the standard library does not provide.	3
markdown	markdown	Helpers for writing Markdown safely: escaping, links, code, quotes, tables and heading anchors.	7
net	net	Network helpers on std::net and plain text: no I/O, no resolution.	3
number	number	Numeric helpers that the standard library does not provide.	7
random	random, random-entropy	Randomness without a hidden global generator.	8
secret	secret	Keeping secrets out of logs: a wrapper that never prints its value, redaction, masking and credential detection.	8
set	set	Helpers for HashSet that the standard library does not provide.	7
string	string, string-diacritics	String manipulation and formatting helpers.	26
time	time	Time helpers.	3
url	url	URLs without a dependency: percent-encoding, query strings, a parser and reference resolution.	8
validate	validate	Shape checks for common user-facing formats: pragmatic subsets that catch real mistakes, not full grammars.	3
version	version	Semantic Versioning 2.0.0: parsing, precedence, bumps and Cargo-style requirements.	5

Import through the module path (helpers4::string::capitalize): names can repeat across modules on purpose, so never glob-import a module.

Documented version: 0.0.11. Minimum supported Rust version: 1.85.