@std/hash

Cryptographic hash functions for checksums, cache keys, ETags, and non-security hashing. All functions take a string and return a lowercase hex-encoded hash string.

let hash = import @std/hash

⚠️ Not for passwords. These are raw hash functions with no salting or key stretching. For password hashing, use Basil's auth system.

Functions

Function	Arguments	Returns	Description
`md5(s)`	`s: string`	32-char hex string	MD5 hash
`sha1(s)`	`s: string`	40-char hex string	SHA1 hash
`sha256(s)`	`s: string`	64-char hex string	SHA256 hash
`sha512(s)`	`s: string`	128-char hex string	SHA512 hash

hash.md5("hello")      // "5d41402abc4b2a76b9719d911017c592"
hash.sha1("hello")     // "aaf4c61ddcc5e8a2dabede0f3b482cd9aea9434d"
hash.sha256("hello")   // "2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824"
hash.sha512("hello")   // "9b71d224bd62f3785d96d46ad3ea3d73..."

Empty strings produce the hash of zero bytes:

hash.md5("")           // "d41d8cd98f00b204e9800998ecf8427e"
hash.sha256("")        // "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"

Unicode strings are hashed as their UTF-8 byte representation:

hash.md5("日本語")     // "00110af8b4393ef3f72c50be5b332bec"

Common Use Cases

ETags for Caching

let hash = import @std/hash

let content = loadPageContent(slug)
let etag = hash.md5(content)

Cache Keys

let hash = import @std/hash

let cacheKey = hash.sha256(userId + ":" + query)

Content Deduplication

let hash = import @std/hash

let digest = hash.sha256(fileContent)
if (digest in knownHashes) {
    "Duplicate detected"
}

Checksums for Data Integrity

let hash = import @std/hash

let checksum = hash.sha256(payload)
// Send checksum alongside payload for verification

Destructuring Import

let { md5, sha256 } = import @std/hash

md5("test")            // "098f6bcd4621d373cade4e832627b4f6"
sha256("test")         // "9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08"

Errors

All functions require exactly one string argument:

hash.md5()             // Error: wrong number of arguments
hash.md5(123)          // Error: expected a string
hash.md5("a", "b")    // Error: wrong number of arguments

Choosing a Hash Function

Function	Speed	Output Size	Use For
`md5`	Fastest	128-bit (32 hex)	ETags, cache keys, non-critical checksums
`sha1`	Fast	160-bit (40 hex)	Git-style content addressing
`sha256`	Moderate	256-bit (64 hex)	Data integrity, deduplication
`sha512`	Moderate	512-bit (128 hex)	When you need a longer digest

MD5 and SHA1 are cryptographically broken for collision resistance but remain fine for checksums and cache keys where adversarial collisions are not a concern.