E0099: count_field_default

E0099 count_field_default — .len / .size read as a field with a default.

A compile-time error of soma check, the checker of the Soma programming language (soma explain E0099).

The rule

On a Map, m.size, m.len and m.length read the number of entries when the map has no key of that name, so m.size ?? 1 never falls back to its default. soma check warns about .size / .len / .length / .keys / .values followed by ??; this binary reports the warning as W0014 (habit_warning), not as E0099. To read a field that is really called size, write m.get("size") ?? 1.

When you see it

soma check never prints E0099: the checker creates this diagnostic as a habit warning, and every habit warning is reported under the warning code W0014 (habit_warning), in edition 2026 and 2027 alike.