iverilog/docs/assoc-array.md

Associative arrays (Tier A #2)

Status: partial — string-keyed vertical slice for UVM-like tables.

Supported in this slice

int aa[string];
int aa[*];          // accepted as string-keyed (not IEEE int-key wildcard yet)
aa["x"] = 1;
v = aa["x"];
n = aa.size();      // also aa.num()
aa.exists("x");
aa.delete("x");
aa.delete();        // clear all
foreach (aa[k]) ... // k is string
bb = aa;            // whole-array copy

Element types: packed integral (int / logic vectors) only for now.

Encoding

Syntax	pform_range_t sentinel
[*]	(PENull, PENull) — distinct from queue (PENull, 0) and darray (0, 0)
[string]	(PETypename(string), 0) via '[' expression ']' (avoids bison conflict with typename-as-expr)

Elaborates to netaarray_t with IVL_VT_AARRAY. Runtime: vvp_aarray_vec4 (std::map<std::string, vvp_vector4_t>).

Deferred (do not claim)

• Integer / class / enum keys (true IEEE [*] integer keys)
• Class / string / real / nested AA elements
• first / last / next / prev methods (foreach uses internal key_at)
• Associative arrays as class properties

See also STATUS.md and ROADMAP.md.