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Tables

The tables module provides table (hash map) operations for the Crux programming language.

Installation​

use table_values, table_keys, table_pairs from "crux:tables";

Methods​

values​

Returns all values in a table as an array.

let t = {"a": 1, "b": 2, "c": 3}
let vals = t.values()  // Result([1, 2, 3])

Returns: Result<Array>

Errors: Failed to allocate memory for values array.

keys​

Returns all keys in a table as an array.

let t = {"a": 1, "b": 2, "c": 3}
let ks = t.keys()  // Result(["a", "b", "c"])

Returns: Result<Array>

Errors: Failed to allocate memory for keys array.

pairs​

Returns all key-value pairs in a table as an array of [key, value] arrays.

let t = {"a": 1, "b": 2}
let ps = t.pairs()  // Result([["a", 1], ["b", 2]])

Returns: Result<Array>

Errors: Failed to allocate memory for pairs array.

remove​

Removes a key-value pair from a table.

let t = {"a": 1, "b": 2}
let result = t.remove("a")  // Result(Nil)

Parameters:

  • key (Hashable): The key to remove

Returns: Result<Nil>

Errors: Failed to remove key-value pair, or unhashable type given as key.

get​

Gets the value associated with a key from a table.

let t = {"a": 1, "b": 2}
let val = t.get("a")  // Result(1)
let missing = t.get("c")  // Error: Failed to get value from table

Parameters:

  • key (Hashable): The key to look up

Returns: Result<Any>

Errors: Failed to get value, or unhashable type given as key.

has_key​

Checks if a table contains a specific key.

let t = {"a": 1, "b": 2}
let has_a = t.has_key("a")  // true
let has_c = t.has_key("c")  // false

Parameters:

  • key (Hashable): The key to check

Returns: Bool

get_or_else​

Gets a value from a table or returns a default if the key doesn't exist.

let t = {"a": 1, "b": 2}
let val = t.get_or_else("a", 0)  // 1
let default = t.get_or_else("c", 99)  // 99

Parameters:

  • key (Hashable): The key to look up
  • default (Any): The default value to return if key not found

Returns: Any