<K1 extends K, K>(key: K1): <V>(self: HashMap<K, V>) => V
<K1 extends K, K, V>(self: HashMap<K, V>, key: K1): VLooks up the value for the specified key in the HashMap unsafely using the
internal hashing function.
When to use
Use when reading from a HashMap by a key known to exist, and throwing is an
acceptable programming error for a missing key.
Gotchas
This function throws an error if the key is not found. Use HashMap.get for
safe access that returns Option.
Example (Unsafely looking up values)
import { HashMap, Option } from "effect"
const config = HashMap.make(
["api_url", "https://api.example.com"],
["timeout", "5000"],
["retries", "3"]
)
// Safe: use when you're certain the key exists
const apiUrl = HashMap.getUnsafe(config, "api_url") // "https://api.example.com"
console.log(`Connecting to: ${apiUrl}`)
// Preferred: use get() for uncertain keys
const dbUrl = HashMap.get(config, "db_url") // Option.none()
if (Option.isSome(dbUrl)) {
console.log(`Database: ${dbUrl.value}`)
}
// This would throw: HashMap.getUnsafe(config, "db_url")
// Error: "HashMap.getUnsafe: key not found"unsafe
Source effect/HashMap.ts:4144 lines
export const const getUnsafe: {
<K1 extends K, K>(key: K1): <V>(
self: HashMap<K, V>
) => V
<K1 extends K, K, V>(
self: HashMap<K, V>,
key: K1
): V
}
Looks up the value for the specified key in the HashMap unsafely using the
internal hashing function.
When to use
Use when reading from a HashMap by a key known to exist, and throwing is an
acceptable programming error for a missing key.
Gotchas
This function throws an error if the key is not found. Use HashMap.get for
safe access that returns Option.
Example (Unsafely looking up values)
import { HashMap, Option } from "effect"
const config = HashMap.make(
["api_url", "https://api.example.com"],
["timeout", "5000"],
["retries", "3"]
)
// Safe: use when you're certain the key exists
const apiUrl = HashMap.getUnsafe(config, "api_url") // "https://api.example.com"
console.log(`Connecting to: ${apiUrl}`)
// Preferred: use get() for uncertain keys
const dbUrl = HashMap.get(config, "db_url") // Option.none()
if (Option.isSome(dbUrl)) {
console.log(`Database: ${dbUrl.value}`)
}
// This would throw: HashMap.getUnsafe(config, "db_url")
// Error: "HashMap.getUnsafe: key not found"
getUnsafe: {
<function (type parameter) K1 in <K1 extends K, K>(key: K1): <V>(self: HashMap<K, V>) => VK1 extends function (type parameter) K in <K1 extends K, K>(key: K1): <V>(self: HashMap<K, V>) => VK, function (type parameter) K in <K1 extends K, K>(key: K1): <V>(self: HashMap<K, V>) => VK>(key: K1 extends Kkey: function (type parameter) K1 in <K1 extends K, K>(key: K1): <V>(self: HashMap<K, V>) => VK1): <function (type parameter) V in <V>(self: HashMap<K, V>): VV>(self: HashMap<K, V>(parameter) self: {
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
interface HashMap<out Key, out Value>A HashMap is an immutable key-value data structure that provides efficient lookup,
insertion, and deletion operations. It uses a Hash Array Mapped Trie (HAMT) internally
for structural sharing and optimal performance.
Example (Using basic HashMap operations)
import { HashMap } from "effect"
// Create a HashMap
const map = HashMap.make(["a", 1], ["b", 2], ["c", 3])
// Access values
const valueA = HashMap.get(map, "a") // Option.some(1)
const valueD = HashMap.get(map, "d") // Option.none()
// Check if key exists
console.log(HashMap.has(map, "b")) // true
// Add/update values (returns new HashMap)
const updated = HashMap.set(map, "d", 4)
console.log(HashMap.size(updated)) // 4
The HashMap namespace contains type-level utilities and helper types
for working with HashMap instances.
Example (Extracting HashMap types)
import { HashMap } from "effect"
// Create a concrete HashMap for type extraction
const inventory = HashMap.make(
["laptop", { quantity: 5, price: 999 }],
["mouse", { quantity: 20, price: 29 }]
)
// Extract types for reuse
type ProductId = HashMap.HashMap.Key<typeof inventory> // string
type Product = HashMap.HashMap.Value<typeof inventory> // { quantity: number, price: number }
type InventoryEntry = HashMap.HashMap.Entry<typeof inventory> // [string, Product]
// Use extracted types in functions
const updateInventory = (id: ProductId, product: Product) =>
HashMap.set(inventory, id, product)
const processEntry = ([id, product]: InventoryEntry) =>
`${id}: ${product.quantity} @ $${product.price}`
// Example of extracted types in action
const newProduct: Product = { quantity: 10, price: 199 }
const updatedInventory = updateInventory("tablet", newProduct)
HashMap<function (type parameter) K in <K1 extends K, K>(key: K1): <V>(self: HashMap<K, V>) => VK, function (type parameter) V in <V>(self: HashMap<K, V>): VV>) => function (type parameter) V in <V>(self: HashMap<K, V>): VV
<function (type parameter) K1 in <K1 extends K, K, V>(self: HashMap<K, V>, key: K1): VK1 extends function (type parameter) K in <K1 extends K, K, V>(self: HashMap<K, V>, key: K1): VK, function (type parameter) K in <K1 extends K, K, V>(self: HashMap<K, V>, key: K1): VK, function (type parameter) V in <K1 extends K, K, V>(self: HashMap<K, V>, key: K1): VV>(self: HashMap<K, V>(parameter) self: {
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
interface HashMap<out Key, out Value>A HashMap is an immutable key-value data structure that provides efficient lookup,
insertion, and deletion operations. It uses a Hash Array Mapped Trie (HAMT) internally
for structural sharing and optimal performance.
Example (Using basic HashMap operations)
import { HashMap } from "effect"
// Create a HashMap
const map = HashMap.make(["a", 1], ["b", 2], ["c", 3])
// Access values
const valueA = HashMap.get(map, "a") // Option.some(1)
const valueD = HashMap.get(map, "d") // Option.none()
// Check if key exists
console.log(HashMap.has(map, "b")) // true
// Add/update values (returns new HashMap)
const updated = HashMap.set(map, "d", 4)
console.log(HashMap.size(updated)) // 4
The HashMap namespace contains type-level utilities and helper types
for working with HashMap instances.
Example (Extracting HashMap types)
import { HashMap } from "effect"
// Create a concrete HashMap for type extraction
const inventory = HashMap.make(
["laptop", { quantity: 5, price: 999 }],
["mouse", { quantity: 20, price: 29 }]
)
// Extract types for reuse
type ProductId = HashMap.HashMap.Key<typeof inventory> // string
type Product = HashMap.HashMap.Value<typeof inventory> // { quantity: number, price: number }
type InventoryEntry = HashMap.HashMap.Entry<typeof inventory> // [string, Product]
// Use extracted types in functions
const updateInventory = (id: ProductId, product: Product) =>
HashMap.set(inventory, id, product)
const processEntry = ([id, product]: InventoryEntry) =>
`${id}: ${product.quantity} @ $${product.price}`
// Example of extracted types in action
const newProduct: Product = { quantity: 10, price: 199 }
const updatedInventory = updateInventory("tablet", newProduct)
HashMap<function (type parameter) K in <K1 extends K, K, V>(self: HashMap<K, V>, key: K1): VK, function (type parameter) V in <K1 extends K, K, V>(self: HashMap<K, V>, key: K1): VV>, key: K1 extends Kkey: function (type parameter) K1 in <K1 extends K, K, V>(self: HashMap<K, V>, key: K1): VK1): function (type parameter) V in <K1 extends K, K, V>(self: HashMap<K, V>, key: K1): VV
} = import internalinternal.const getUnsafe: anygetUnsafe