aver/types/
map.rs

1/// Map namespace — immutable key/value map helpers.
2///
3/// Methods:
4///   Map.empty()                 → Map<K, V>
5///   Map.set(map, key, value)    → Map<K, V>
6///   Map.get(map, key)           → Option<V>
7///   Map.remove(map, key)        → Map<K, V>
8///   Map.has(map, key)           → Bool
9///   Map.keys(map)               → List<K>
10///   Map.values(map)             → List<V>
11///   Map.entries(map)            → List<(K, V)>
12///   Map.len(map)                → Int
13///   Map.fromList(pairs)         → Map<K, V> where each pair is (key, value)
14///
15/// Key constraint: only scalar keys are allowed (Int, Float, String, Bool).
16///
17/// No effects required.
18use std::cmp::Ordering;
19use std::collections::HashMap;
20use std::rc::Rc;
21
22use crate::nan_value::{Arena, NanValue};
23use crate::value::{RuntimeError, Value, aver_repr, list_from_vec, list_view};
24
25pub fn register(global: &mut HashMap<String, Value>) {
26    let mut members = HashMap::new();
27    for method in &[
28        "empty", "set", "get", "remove", "has", "keys", "values", "entries", "len", "fromList",
29    ] {
30        members.insert(
31            method.to_string(),
32            Value::Builtin(format!("Map.{}", method)),
33        );
34    }
35    global.insert(
36        "Map".to_string(),
37        Value::Namespace {
38            name: "Map".to_string(),
39            members,
40        },
41    );
42}
43
44pub fn effects(_name: &str) -> &'static [&'static str] {
45    &[]
46}
47
48/// Returns `Some(result)` when `name` is owned by this namespace, `None` otherwise.
49pub fn call(name: &str, args: &[Value]) -> Option<Result<Value, RuntimeError>> {
50    match name {
51        "Map.empty" => Some(empty(args)),
52        "Map.set" => Some(set(args)),
53        "Map.get" => Some(get(args)),
54        "Map.remove" => Some(remove(args)),
55        "Map.has" => Some(has(args)),
56        "Map.keys" => Some(keys(args)),
57        "Map.values" => Some(values(args)),
58        "Map.entries" => Some(entries(args)),
59        "Map.len" => Some(len(args)),
60        "Map.fromList" => Some(from_list(args)),
61        _ => None,
62    }
63}
64
65fn empty(args: &[Value]) -> Result<Value, RuntimeError> {
66    if !args.is_empty() {
67        return Err(RuntimeError::Error(format!(
68            "Map.empty() takes 0 arguments, got {}",
69            args.len()
70        )));
71    }
72    Ok(Value::Map(HashMap::new()))
73}
74
75fn set(args: &[Value]) -> Result<Value, RuntimeError> {
76    let [map_val, key, value] = three_args("Map.set", args)?;
77    let Value::Map(map) = map_val else {
78        return Err(RuntimeError::Error(
79            "Map.set() first argument must be a Map".to_string(),
80        ));
81    };
82    ensure_hashable_key("Map.set", key)?;
83    let mut out = map.clone();
84    out.insert(key.clone(), value.clone());
85    Ok(Value::Map(out))
86}
87
88fn get(args: &[Value]) -> Result<Value, RuntimeError> {
89    let [map_val, key] = two_args("Map.get", args)?;
90    let Value::Map(map) = map_val else {
91        return Err(RuntimeError::Error(
92            "Map.get() first argument must be a Map".to_string(),
93        ));
94    };
95    ensure_hashable_key("Map.get", key)?;
96    Ok(match map.get(key) {
97        Some(v) => Value::Some(Box::new(v.clone())),
98        None => Value::None,
99    })
100}
101
102fn remove(args: &[Value]) -> Result<Value, RuntimeError> {
103    let [map_val, key] = two_args("Map.remove", args)?;
104    let Value::Map(map) = map_val else {
105        return Err(RuntimeError::Error(
106            "Map.remove() first argument must be a Map".to_string(),
107        ));
108    };
109    ensure_hashable_key("Map.remove", key)?;
110    let mut out = map.clone();
111    out.remove(key);
112    Ok(Value::Map(out))
113}
114
115fn has(args: &[Value]) -> Result<Value, RuntimeError> {
116    let [map_val, key] = two_args("Map.has", args)?;
117    let Value::Map(map) = map_val else {
118        return Err(RuntimeError::Error(
119            "Map.has() first argument must be a Map".to_string(),
120        ));
121    };
122    ensure_hashable_key("Map.has", key)?;
123    Ok(Value::Bool(map.contains_key(key)))
124}
125
126fn keys(args: &[Value]) -> Result<Value, RuntimeError> {
127    let [map_val] = one_arg("Map.keys", args)?;
128    let Value::Map(map) = map_val else {
129        return Err(RuntimeError::Error(
130            "Map.keys() argument must be a Map".to_string(),
131        ));
132    };
133    let mut out = map.keys().cloned().collect::<Vec<_>>();
134    out.sort_by(compare_scalar_keys);
135    Ok(list_from_vec(out))
136}
137
138fn values(args: &[Value]) -> Result<Value, RuntimeError> {
139    let [map_val] = one_arg("Map.values", args)?;
140    let Value::Map(map) = map_val else {
141        return Err(RuntimeError::Error(
142            "Map.values() argument must be a Map".to_string(),
143        ));
144    };
145    let mut entries = map.iter().collect::<Vec<_>>();
146    entries.sort_by(|(k1, _), (k2, _)| compare_scalar_keys(k1, k2));
147    let out = entries
148        .into_iter()
149        .map(|(_, v)| v.clone())
150        .collect::<Vec<_>>();
151    Ok(list_from_vec(out))
152}
153
154fn entries(args: &[Value]) -> Result<Value, RuntimeError> {
155    let [map_val] = one_arg("Map.entries", args)?;
156    let Value::Map(map) = map_val else {
157        return Err(RuntimeError::Error(
158            "Map.entries() argument must be a Map".to_string(),
159        ));
160    };
161    let mut entries = map.iter().collect::<Vec<_>>();
162    entries.sort_by(|(k1, _), (k2, _)| compare_scalar_keys(k1, k2));
163    let out = entries
164        .into_iter()
165        .map(|(k, v)| Value::Tuple(vec![k.clone(), v.clone()]))
166        .collect::<Vec<_>>();
167    Ok(list_from_vec(out))
168}
169
170fn len(args: &[Value]) -> Result<Value, RuntimeError> {
171    let [map_val] = one_arg("Map.len", args)?;
172    let Value::Map(map) = map_val else {
173        return Err(RuntimeError::Error(
174            "Map.len() argument must be a Map".to_string(),
175        ));
176    };
177    Ok(Value::Int(map.len() as i64))
178}
179
180fn from_list(args: &[Value]) -> Result<Value, RuntimeError> {
181    let [pairs] = one_arg("Map.fromList", args)?;
182    let items = list_view(pairs).ok_or_else(|| {
183        RuntimeError::Error(
184            "Map.fromList() argument must be a List of (key, value) tuples".to_string(),
185        )
186    })?;
187
188    let mut out = HashMap::new();
189    for (idx, pair) in items.iter().enumerate() {
190        let Value::Tuple(parts) = pair else {
191            return Err(RuntimeError::Error(format!(
192                "Map.fromList() item {} must be (key, value)",
193                idx + 1
194            )));
195        };
196        if parts.len() != 2 {
197            return Err(RuntimeError::Error(format!(
198                "Map.fromList() item {} must have 2 elements",
199                idx + 1
200            )));
201        }
202
203        let key = &parts[0];
204        let value = &parts[1];
205        ensure_hashable_key("Map.fromList", key)?;
206        out.insert(key.clone(), value.clone());
207    }
208    Ok(Value::Map(out))
209}
210
211fn is_hashable_key(value: &Value) -> bool {
212    matches!(
213        value,
214        Value::Int(_) | Value::Float(_) | Value::Str(_) | Value::Bool(_)
215    )
216}
217
218fn ensure_hashable_key(name: &str, value: &Value) -> Result<(), RuntimeError> {
219    if is_hashable_key(value) {
220        Ok(())
221    } else {
222        Err(RuntimeError::Error(format!(
223            "{}: key must be Int, Float, String, or Bool",
224            name
225        )))
226    }
227}
228
229fn compare_scalar_keys(a: &Value, b: &Value) -> Ordering {
230    match (a, b) {
231        (Value::Int(x), Value::Int(y)) => x.cmp(y),
232        (Value::Float(x), Value::Float(y)) => x.partial_cmp(y).unwrap_or_else(|| {
233            let xb = x.to_bits();
234            let yb = y.to_bits();
235            xb.cmp(&yb)
236        }),
237        (Value::Str(x), Value::Str(y)) => x.cmp(y),
238        (Value::Bool(x), Value::Bool(y)) => x.cmp(y),
239        _ => aver_repr(a).cmp(&aver_repr(b)),
240    }
241}
242
243fn one_arg<'a>(name: &str, args: &'a [Value]) -> Result<[&'a Value; 1], RuntimeError> {
244    if args.len() != 1 {
245        return Err(RuntimeError::Error(format!(
246            "{}() takes 1 argument, got {}",
247            name,
248            args.len()
249        )));
250    }
251    Ok([&args[0]])
252}
253
254fn two_args<'a>(name: &str, args: &'a [Value]) -> Result<[&'a Value; 2], RuntimeError> {
255    if args.len() != 2 {
256        return Err(RuntimeError::Error(format!(
257            "{}() takes 2 arguments, got {}",
258            name,
259            args.len()
260        )));
261    }
262    Ok([&args[0], &args[1]])
263}
264
265fn three_args<'a>(name: &str, args: &'a [Value]) -> Result<[&'a Value; 3], RuntimeError> {
266    if args.len() != 3 {
267        return Err(RuntimeError::Error(format!(
268            "{}() takes 3 arguments, got {}",
269            name,
270            args.len()
271        )));
272    }
273    Ok([&args[0], &args[1], &args[2]])
274}
275
276// ─── NanValue-native API ─────────────────────────────────────────────────────
277
278pub fn register_nv(global: &mut HashMap<String, NanValue>, arena: &mut Arena) {
279    let methods = &[
280        "empty", "set", "get", "remove", "has", "keys", "values", "entries", "len", "fromList",
281    ];
282    let mut members: Vec<(Rc<str>, NanValue)> = Vec::with_capacity(methods.len());
283    for method in methods {
284        let idx = arena.push_builtin(&format!("Map.{}", method));
285        members.push((Rc::from(*method), NanValue::new_builtin(idx)));
286    }
287    let ns_idx = arena.push(crate::nan_value::ArenaEntry::Namespace {
288        name: Rc::from("Map"),
289        members,
290    });
291    global.insert("Map".to_string(), NanValue::new_namespace(ns_idx));
292}
293
294pub fn call_nv(
295    name: &str,
296    args: &[NanValue],
297    arena: &mut Arena,
298) -> Option<Result<NanValue, RuntimeError>> {
299    match name {
300        "Map.empty" => Some(empty_nv(args, arena)),
301        "Map.set" => Some(set_nv(args, arena)),
302        "Map.get" => Some(get_nv(args, arena)),
303        "Map.remove" => Some(remove_nv(args, arena)),
304        "Map.has" => Some(has_nv(args, arena)),
305        "Map.keys" => Some(keys_nv(args, arena)),
306        "Map.values" => Some(values_nv(args, arena)),
307        "Map.entries" => Some(entries_nv(args, arena)),
308        "Map.len" => Some(len_nv(args, arena)),
309        "Map.fromList" => Some(from_list_nv(args, arena)),
310        _ => None,
311    }
312}
313
314fn is_hashable_nv(v: NanValue) -> bool {
315    v.is_int() || v.is_float() || v.is_string() || v.is_bool()
316}
317
318fn ensure_hashable_nv(name: &str, v: NanValue) -> Result<(), RuntimeError> {
319    if is_hashable_nv(v) {
320        Ok(())
321    } else {
322        Err(RuntimeError::Error(format!(
323            "{}: key must be Int, Float, String, or Bool",
324            name
325        )))
326    }
327}
328
329fn nv_key_bits(v: NanValue, arena: &Arena) -> u64 {
330    v.map_key_hash(arena)
331}
332
333fn empty_nv(args: &[NanValue], arena: &mut Arena) -> Result<NanValue, RuntimeError> {
334    if !args.is_empty() {
335        return Err(RuntimeError::Error(format!(
336            "Map.empty() takes 0 arguments, got {}",
337            args.len()
338        )));
339    }
340    let map_idx = arena.push_map(crate::nan_value::PersistentMap::new());
341    Ok(NanValue::new_map(map_idx))
342}
343
344fn set_nv(args: &[NanValue], arena: &mut Arena) -> Result<NanValue, RuntimeError> {
345    if args.len() != 3 {
346        return Err(RuntimeError::Error(format!(
347            "Map.set() takes 3 arguments, got {}",
348            args.len()
349        )));
350    }
351    if !args[0].is_map() {
352        return Err(RuntimeError::Error(
353            "Map.set() first argument must be a Map".to_string(),
354        ));
355    }
356    ensure_hashable_nv("Map.set", args[1])?;
357    let old_map = arena.get_map(args[0].arena_index()).clone();
358    let mut new_map = old_map;
359    let key_hash = nv_key_bits(args[1], arena);
360    new_map.insert(key_hash, (args[1], args[2]));
361    let map_idx = arena.push_map(new_map);
362    Ok(NanValue::new_map(map_idx))
363}
364
365fn get_nv(args: &[NanValue], arena: &mut Arena) -> Result<NanValue, RuntimeError> {
366    if args.len() != 2 {
367        return Err(RuntimeError::Error(format!(
368            "Map.get() takes 2 arguments, got {}",
369            args.len()
370        )));
371    }
372    if !args[0].is_map() {
373        return Err(RuntimeError::Error(
374            "Map.get() first argument must be a Map".to_string(),
375        ));
376    }
377    ensure_hashable_nv("Map.get", args[1])?;
378    let key_hash = nv_key_bits(args[1], arena);
379    let map = arena.get_map(args[0].arena_index());
380    match map.get(&key_hash) {
381        Some((_, v)) => {
382            let box_idx = arena.push_boxed(*v);
383            Ok(NanValue::new_some(box_idx))
384        }
385        None => Ok(NanValue::NONE),
386    }
387}
388
389fn remove_nv(args: &[NanValue], arena: &mut Arena) -> Result<NanValue, RuntimeError> {
390    if args.len() != 2 {
391        return Err(RuntimeError::Error(format!(
392            "Map.remove() takes 2 arguments, got {}",
393            args.len()
394        )));
395    }
396    if !args[0].is_map() {
397        return Err(RuntimeError::Error(
398            "Map.remove() first argument must be a Map".to_string(),
399        ));
400    }
401    ensure_hashable_nv("Map.remove", args[1])?;
402    let old_map = arena.get_map(args[0].arena_index()).clone();
403    let mut new_map = old_map;
404    let key_hash = nv_key_bits(args[1], arena);
405    new_map.remove(&key_hash);
406    let map_idx = arena.push_map(new_map);
407    Ok(NanValue::new_map(map_idx))
408}
409
410fn has_nv(args: &[NanValue], arena: &mut Arena) -> Result<NanValue, RuntimeError> {
411    if args.len() != 2 {
412        return Err(RuntimeError::Error(format!(
413            "Map.has() takes 2 arguments, got {}",
414            args.len()
415        )));
416    }
417    if !args[0].is_map() {
418        return Err(RuntimeError::Error(
419            "Map.has() first argument must be a Map".to_string(),
420        ));
421    }
422    ensure_hashable_nv("Map.has", args[1])?;
423    let key_hash = nv_key_bits(args[1], arena);
424    let map = arena.get_map(args[0].arena_index());
425    Ok(NanValue::new_bool(map.contains_key(&key_hash)))
426}
427
428fn keys_nv(args: &[NanValue], arena: &mut Arena) -> Result<NanValue, RuntimeError> {
429    if args.len() != 1 {
430        return Err(RuntimeError::Error(format!(
431            "Map.keys() takes 1 argument, got {}",
432            args.len()
433        )));
434    }
435    if !args[0].is_map() {
436        return Err(RuntimeError::Error(
437            "Map.keys() argument must be a Map".to_string(),
438        ));
439    }
440    let map = arena.get_map(args[0].arena_index()).clone();
441    let mut keys: Vec<NanValue> = map.values().map(|(k, _)| *k).collect();
442    keys.sort_by_key(|a| a.repr(arena));
443    let list_idx = arena.push_list(keys);
444    Ok(NanValue::new_list(list_idx))
445}
446
447fn values_nv(args: &[NanValue], arena: &mut Arena) -> Result<NanValue, RuntimeError> {
448    if args.len() != 1 {
449        return Err(RuntimeError::Error(format!(
450            "Map.values() takes 1 argument, got {}",
451            args.len()
452        )));
453    }
454    if !args[0].is_map() {
455        return Err(RuntimeError::Error(
456            "Map.values() argument must be a Map".to_string(),
457        ));
458    }
459    let map = arena.get_map(args[0].arena_index()).clone();
460    let mut entries: Vec<(NanValue, NanValue)> = map.values().cloned().collect();
461    entries.sort_by(|(a, _), (b, _)| a.repr(arena).cmp(&b.repr(arena)));
462    let vals: Vec<NanValue> = entries.into_iter().map(|(_, v)| v).collect();
463    let list_idx = arena.push_list(vals);
464    Ok(NanValue::new_list(list_idx))
465}
466
467fn entries_nv(args: &[NanValue], arena: &mut Arena) -> Result<NanValue, RuntimeError> {
468    if args.len() != 1 {
469        return Err(RuntimeError::Error(format!(
470            "Map.entries() takes 1 argument, got {}",
471            args.len()
472        )));
473    }
474    if !args[0].is_map() {
475        return Err(RuntimeError::Error(
476            "Map.entries() argument must be a Map".to_string(),
477        ));
478    }
479    let map = arena.get_map(args[0].arena_index()).clone();
480    let mut entries: Vec<(NanValue, NanValue)> = map.values().cloned().collect();
481    entries.sort_by(|(a, _), (b, _)| a.repr(arena).cmp(&b.repr(arena)));
482    let pairs: Vec<NanValue> = entries
483        .into_iter()
484        .map(|(k, v)| {
485            let tuple_idx = arena.push_tuple(vec![k, v]);
486            NanValue::new_tuple(tuple_idx)
487        })
488        .collect();
489    let list_idx = arena.push_list(pairs);
490    Ok(NanValue::new_list(list_idx))
491}
492
493fn len_nv(args: &[NanValue], arena: &mut Arena) -> Result<NanValue, RuntimeError> {
494    if args.len() != 1 {
495        return Err(RuntimeError::Error(format!(
496            "Map.len() takes 1 argument, got {}",
497            args.len()
498        )));
499    }
500    if !args[0].is_map() {
501        return Err(RuntimeError::Error(
502            "Map.len() argument must be a Map".to_string(),
503        ));
504    }
505    let map = arena.get_map(args[0].arena_index());
506    Ok(NanValue::new_int(map.len() as i64, arena))
507}
508
509fn from_list_nv(args: &[NanValue], arena: &mut Arena) -> Result<NanValue, RuntimeError> {
510    if args.len() != 1 {
511        return Err(RuntimeError::Error(format!(
512            "Map.fromList() takes 1 argument, got {}",
513            args.len()
514        )));
515    }
516    if !args[0].is_list() {
517        return Err(RuntimeError::Error(
518            "Map.fromList() argument must be a List of (key, value) tuples".to_string(),
519        ));
520    }
521    let items = arena.list_to_vec(args[0].arena_index());
522    let mut out = crate::nan_value::PersistentMap::new();
523    for (idx, pair) in items.iter().enumerate() {
524        if !pair.is_tuple() {
525            return Err(RuntimeError::Error(format!(
526                "Map.fromList() item {} must be (key, value)",
527                idx + 1
528            )));
529        }
530        let parts = arena.get_tuple(pair.arena_index());
531        if parts.len() != 2 {
532            return Err(RuntimeError::Error(format!(
533                "Map.fromList() item {} must have 2 elements",
534                idx + 1
535            )));
536        }
537        let key = parts[0];
538        let value = parts[1];
539        ensure_hashable_nv("Map.fromList", key)?;
540        let key_hash = nv_key_bits(key, arena);
541        out.insert(key_hash, (key, value));
542    }
543    let map_idx = arena.push_map(out);
544    Ok(NanValue::new_map(map_idx))
545}
aver/types/map.rs

aver/types/
map.rs
