Dict¶

A Dict maps a keys collection to a values collection (type code 99). Keys are typically a symbol vector and values any Value — a vector, a list, or another dict. A dict whose values are equal-length vectors is the building block of a table.

Assume a live runtime

use rayforce::{Runtime, Value};
let _rt = Runtime::new()?;

Construction¶

Value::dict(keys, values) takes two Values — the keys and the values.

let keys = Value::sym_vec(&["a", "b", "c"]);
let vals = Value::vec(&[1i64, 2, 3]);
let d = Value::dict(keys, vals);

assert!(d.is_dict());
assert_eq!(d.dict_len()?, 3);

Accessing keys and values¶

let keys = Value::sym_vec(&["a", "b", "c"]);
let vals = Value::vec(&[1i64, 2, 3]);
let d = Value::dict(keys, vals);

// The whole keys / values collections
assert_eq!(d.dict_keys()?.get(0)?.as_sym()?, "a");
assert_eq!(d.dict_values()?.as_slice::<i64>()?, &[1, 2, 3]);

Lookup¶

dict_get returns Result<Option<Value>>: Ok(Some(..)) on a hit, Ok(None) when the key is absent.

let keys = Value::sym_vec(&["a", "b", "c"]);
let vals = Value::vec(&[1i64, 2, 3]);
let d = Value::dict(keys, vals);

let got = d.dict_get(&Value::sym("b"))?;
assert_eq!(got.unwrap().as_i64()?, 2);

assert!(d.dict_get(&Value::sym("missing"))?.is_none());

Dict is the path to Table

A dict of symbol keys → equal-length vector values is exactly a column-major table. When you need named columns with row semantics, build a Table instead of querying a raw dict.